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c#条�g�~�译

天下 — Wed, 26 Jun 2019 10:03:00 GMT

Conditional compilation symbols

�~�译器命令行选项�Q�例如，/define:DEBUG�Q?

可以在VS2008的IDE�q�行讄��, Project Property--->Build--->Conditional compilation symbols(如果多个�U�研使用逗号隔开)

�pȝ��默认讄��?DEBUG �?TRACE

操作�pȝ��外壳�E�序中的环境变量�Q�例如，set DEBUG=1�Q��?/div>

源代码中的杂注（例如�Q�用于定义编译变量的 #define DEBUG�Q�以及用于取消定义它�?#undef DEBUG�Q��?/div>

必须在file的最前方讄��,#define debug或者组合操�?/div>

#if (Debug && Trace)

#define DebugAndTrace

#endif

ps:Conditional位于using System.Diagnostics;

什么情况下使用该标识符?

当程序中一个方法或属性不惛_��使用�?如果把它删掉��需要把引用的地方一个一个全部删掉不然就会编译错�?�q�时我们��可以在塔的上面加一个[Conditional("string")] 然后�E�序�q�行时就会忽略它

ps:[Conditional("string")]里面字符串随意取

如果惛_��ơ调用那个方法或属性怎么�?

�q�个很简�?你只需在引用命名空间那个地方进行一个宏定义把你在[Conditional("string")]里面的字�W�串定义出来��p��用了

C#-#define条�g�~�译

C#的预处理器指令从来不会�{化�ؓ可执行代码的命��o�Q�但是会影响�~�译�q�程的各个方面，常用的预处理器指令有#define�?undef�?if,#elif,#else�?endif�{�等�Q�下面介�l�C#中��?define�q�行条�g�~�译的实例�?/div>

C#中条件编译指令用于按条�g包含或排除源文�g中的某些部分。在Visual Studio中，会看到被排除的代码显�C�Zؓ灰色�?/div>

一�?define可以用来做什�?/div>

1、当计划发布两个版本的代码的时候。即基本版和拥有更多版本的企业版�Q�就可以用到条�g�~�译指��o�Q?/div>

2、例如同一个文件给silverlight、wpf、winform�{��用，�q�且�q�考虑Debug和Release�{�，有大部分代码是一��L��Q?/div>

3、指定函数和属性是否编译到最�l��品中厅R�?/div>

二�?define用法

语法�Q?define 名称

注意�Q�这里名�U�取Debug�Q�你也可以取其他名称如Dragon

1 #define Debug

说明�Q?/div>

1、Debug可以看做是声明的一个变量，但此变量没有真正的��|��存在�?if Debug�l�果为true�Q�否则�ؓfalse�Q?/div>

2�?define单独用没什么意义，一般是�?if或者Conditional�Ҏ(gu��)��结合��用；

3�?define必须定义在所有using命名�I�间前面�Q?/div>

4、Debug与DEBUG是不同的�Q�C#区分大小�?/div>

天下 2019-06-26 18:03 发表评论

C# invoke,BeginInvoke,EndInvoke

天下 — Thu, 08 Sep 2016 02:16:00 GMT

C# invoke,BeginInvoke,EndInvoke
在多�U�程�~�程中，我们�l�常要在工作�U�程中去更新界面昄��Q�而在多线�E�中直接调用界面控�g的方法是错误的做法，Invoke �?nbsp;BeginInvoke ��是��Z��解决�q�个问题而出现的�Q��你在多线�E�中安全的更新界面显�C��?br />正确的做法是��工作线�E�中涉及更新界面的代码封装�ؓ一个方法，通过 Invoke 或�?nbsp;BeginInvoke 去调用，两者的区别��是一个导致工作线�E�等待，而另外一个则不会�?br />再�D个简单例子说明下使用�Ҏ(gu��)��,比如你在启动一个线�E?在线�E�的�Ҏ(gu��)��中想更新�H�体中的一个TextBox..

using System.Threading;
//启动一个线�E?nbsp;
Thread thread=new Thread(new ThreadStart(DoWork));
thread.Start();
//�U�程�Ҏ(gu��)��
private void DoWork()
{
    this.TextBox1.Text="我是一个文本框";
}
如果你像上面操作,在VS2005�?008里是会有异常�?img src="http://www.shnenglu.com/Images/dot.gif" alt="" />

正确的做法是用Invoke\BeginInvoke
using System.Threading;
namespace test
{
    public partial class Form1 : Form
    {
        public delegate void MyInvoke(string str1,string str2);
        public Form1()
        {
            InitializeComponent();
        }
        public void DoWork()
        {
            MyInvoke mi = new MyInvoke(UpdateForm);
            this.BeginInvoke(mi, new Object[] {"我是文本�?/span>","haha"});
        }
        public void UpdateForm(string param1,string parm2)
        {
            this.textBox1.Text = param1+parm2;
        }
        private void button1_Click(object sender, EventArgs e)
        {
            Thread thread = new Thread(new ThreadStart(DoWork));
            thread.Start();
        }
    }
}

相关资料�Q�Invoke �?nbsp;BeginInvoke 的真正涵�?nbsp;、在多线�E�中如何调用Winform
Control.BeginInvoke �Ҏ(gu��)��  Visual Studio 2010Visual Studio 2010
在创建控件的基础句柄所在线�E�上异步执行委托�?br />公共�Ҏ(gu��)�� BeginInvoke(Delegate) 在创建控件的基础句柄所在线�E�上异步执行指定委托�?nbsp;
公共�Ҏ(gu��)�� BeginInvoke(Delegate,Object[])  在创建控件的基础句柄所在线�E�上�Q�用指定的参数异步执行指定委托�?nbsp;
public Object EndInvoke(IAsyncResult asyncResult)
参数�Q�asyncResult �c�d��Q�System.IAsyncResult
IAsyncResult�Q�表�C�特定的调用异步操作�Q�在调用 BeginInvoke 时返回�?nbsp;

天下 2016-09-08 10:16 发表评论

String.Format

天下 — Fri, 02 Sep 2016 06:23:00 GMT

每个格式��w��采用下面的�Ş式�ƈ包含以下�l��g�Q?/span>

{索引[,寚w��][:格式字符�?/span>]}

必须使用成对的大括号�Q?/span>“{”�?/span>“}”�Q��?/span>

转义大括�?/span>

左大括号和右大括可��解释为格式项的开始和�l�束。因此，必须使用转义序列昄��文本左大括号或右大括受��在固定文本中指定两个左大括�?/span> ("{{") 以显�C�Z��个左大括�?/span> ("{")�Q�或指定两个叛_��括号 ("}}") 以显�C�Z��个右大括�?/span> ("}")。按照在格式��中遇到大括��L��序依次解释它们。不支持解释嵌套的大括号�?/span>

下表描述了每个标准格式说明符的标准格式模式，以及可通过讄��来修�Ҏ(gu��)��准格式的兌�� NumberFormatInfo 属性�?/span>

ms-help://MS.VSCC.v90/MS.MSDNQTR.v90.chs/fxref_mscorlib/html/b42c00a5-84e5-51a1-b7e4-6aaae8dac25b.htm

ms-help://MS.VSCC.v90/MS.MSDNQTR.v90.chs/dv_fxfund/html/580e57eb-ac47-4ffd-bccd-3a1637c2f467.htm

格式模式	说明和关联属�?/span>
c�?/span>C	货币格式
d�?/span>D	十进制格�?/span>
e�?/span>E	�U�学计数�Q�指敎ͼ�格式
f�?/span>F	固定�Ҏ(gu��)��?/span>
g�?/span>G	常规格式
n�?/span>N	数字格式
p�?/span>P	癑ֈ�比格�?/span>
r�?/span>R	往�q�格�?/span>
x�?/span>X	十六�q�制格式

天下 2016-09-02 14:23 发表评论

C#基础知识加强�Q�值类型，应用�c�d��

天下 — Fri, 02 Sep 2016 01:18:00 GMT

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using TK;
namespace ConsoleTester
{
    class Program
    {
        public class SomeRef
        {
            public Int32 x;
        }
        public struct SomeVal
        {
            public Int32 x;
        }
        static void Main(string[] args)
        {
            var r1 = new SomeRef(); //堆上分配
            var v1 = new SomeVal(); //栈上分配�Q�同时确保值类型字�D�初始化�?.

            r1.x = 5;
            v1.x = 6;

            SomeRef r2 = r1;
            r2.x = 7;
            Console.WriteLine("r1.x={0}", r1.x);
            Console.WriteLine("r2.x={0}", r2.x);

            var v2 = v1;
            v2.x = 8;

            Console.WriteLine("v1.x={0}", v1.x);
            Console.WriteLine("v2.x={0}", v2.x);

            Console.Read();

        }
    }
}

天下 2016-09-02 09:18 发表评论

C++ CLI 可变参数

天下 — Thu, 01 Sep 2016 06:48:00 GMT

namespace TK
{
    public enum class LogLevel { Kernel, Fatal, Error, Warning, Infomation, Debug};
    public ref class LogHelper
    {
    public:
        static bool Open(String^ filename);
        static void Close();
        static bool Write(LogLevel level,String^ format, array^ args);
        static bool WriteLine(LogLevel level,String^ format, array^ args);
        static void SetLevel(LogLevel level);
    };
}

static void MarshalString(String^ net, CString& os) {
    LPCTSTR chars = (LPCTSTR)(Marshal::StringToHGlobalUni(net)).ToPointer();
    os = chars;
    Marshal::FreeHGlobal(IntPtr((void*)chars));
}
#pragma unmanaged
static CStringA CStrW2CStrA(const CStringW &cstrSrcW)
{
    int len = WideCharToMultiByte(CP_UTF8, 0, LPCWSTR(cstrSrcW), -1, NULL, 0, NULL, NULL);
    char *str = new char[len];
    memset(str, 0, len);
    WideCharToMultiByte(CP_UTF8, 0, LPCWSTR(cstrSrcW), -1, str, len, NULL, NULL);
    CStringA cstrDestA = str;
    delete[] str;

    return cstrDestA;
}
#pragma managed

天下 2016-09-01 14:48 发表评论

Dev Express 一些Tips

天下 — Thu, 21 Jul 2016 01:54:00 GMT

Dev Express

Skin Libraries
Skins for DevExpress components are shipped in compiled libraries. To apply a skin, ensure that a corresponding library is added to the References section of your project.

Common Skins
The DevExpress.Utils.v15.2.dll library contains common skins such as the DevExpress Style, Office 2013, VS2010, Office 2010 Blue, etc. This library is automatically added to the References section of your project when any DevExpress control/component is added to the form.

Extra Skins
Certain additional skins are available in the DevExpress.BonusSkins.v15.2.dll library, which must be manually added to the References section if you need to use any of these bonus skins.

Custom Skins
You can customize any common or extra skin by creating a custom skin using the WinForms Skin Editor utility. The WinForms Skin Editor creates a skin library (.dll) containing custom skins. The created library must be manually added to the References section of your project.

Note
To use any extra or custom skin at runtime, you need to add the skin library registration code. See the Bonus and Custom Skin Registration topic to learn more.
[STAThread]
static void Main() {
    // Skin registration.
    DevExpress.UserSkins.BonusSkins.Register();
    Application.Run(new Form1());
}

使动态皮肤即�ȝ��?br />It is possible to call the EnableFormSkins() method later, after the application startup. In this instance, the DevExpress.LookAndFeel.LookAndFeelHelper.ForceDefaultLookAndFeelChanged method needs to be called after the call to EnableFormSkins(). This forces the form's title bar to be repainted.
DevExpress.Skins.SkinManager.EnableFormSkins();
DevExpress.LookAndFeel.LookAndFeelHelper.ForceDefaultLookAndFeelChanged();
或�?br />DevExpress.Skins.SkinManager.DisableFormSkins();
DevExpress.LookAndFeel.LookAndFeelHelper.ForceDefaultLookAndFeelChanged();

动态换皮肤
//��d��控�g comboBoxEdit1
public partial class Form1 :  DevExpress.XtraEditors.XtraForm
{
    public Form1()
    {
        InitializeComponent();
        foreach (SkinContainer cnt in SkinManager.Default.Skins)
            comboBoxEdit1.Properties.Items.Add(cnt.SkinName);
        comboBoxEdit1.SelectedIndexChanged += new EventHandler(comboBoxEdit1_SelectedIndexChanged);
    }
    void comboBoxEdit1_SelectedIndexChanged(object sender, EventArgs e)
    {
        ComboBoxEdit comboBox = sender as ComboBoxEdit;
        string skinName = comboBox.Text;
        //DevExpress.LookAndFeel.UserLookAndFeel.Default.SkinName = skinName;
        this.LookAndFeel.SkinName = skinName;
    }
}

//using DevExpress.XtraBars.Helpers;
    public partial class Form1 :  DevExpress.XtraEditors.XtraForm
    {
        public Form1()
        {
            InitializeComponent();
            this.barManager1.ForceInitialize();
            alertControl1.BeforeFormShow += alertControl1_BeforeFormShow;

            //��止barManage右键昄��
            this.barManager1.AllowCustomization = false;
            this.barManager1.AllowShowToolbarsPopup = false;
            //去除barManage双��三�?nbsp;自定�?/span>
            this.barManager1.AllowQuickCustomization = false;

            this.LookAndFeel.UseDefaultLookAndFeel = true;
            //��d��一个BarSubItem DevExpress.XtraBars.BarSubItem mPaintStyle;
            //��d��换肤
            SkinHelper.InitSkinPopupMenu(mPaintStyle);

            //标题栏支持皮�?/span>
            DevExpress.Skins.SkinManager.EnableFormSkins();
        }
}

天下 2016-07-21 09:54 发表评论

C#关键字implicit �?explicit

天下 — Fri, 17 Jun 2016 06:06:00 GMT

C#关键字implicit �?nbsp;explicit

explicit�Q�C# 参考）
explicit 关键字用于声明必��M��用强制�{换来调用的用户定义的�c�d��转换�q�算�W��?nbsp;例如�Q�在下面的示例中�Q�此�q�算�W�将名�ؓ Fahrenheit 的类转换为名�?nbsp;Celsius 的类�Q?br />// Must be defined inside a class called Fahrenheit:
public static explicit operator Celsius(Fahrenheit fahr)
{
    return new Celsius((5.0f / 9.0f) * (fahr.degrees - 32));
}
可以如下所�C��用此转换�q�算�W�：
Fahrenheit fahr = new Fahrenheit(100.0f);
Console.Write("{0} Fahrenheit", fahr.Degrees);
Celsius c = (Celsius)fahr;
转换�q�算�W�将源类型�{换�ؓ目标�c�d��?nbsp;源类型提供�{换运��符�?nbsp;与隐式�{换不同，必须通过强制转换的方式来调用昑ּ�转换�q�算�W��?nbsp;如果转换操作可能��D��异常或丢�׃��息，则应��其标记�?nbsp;explicit�?nbsp;�q�可以防止编译器无提�C�地调用可能产生无法预见后果的�{换操作�?br />省略此强制�{换将��D��~�译旉��?nbsp;CS0266�?br />
implicit�Q�C# 参考）
implicit 关键字用于声明隐式的用户定义�c�d��转换�q�算�W��?nbsp;如果可以��保转换�q�程不会造成数据丢失�Q�则可��用该关键字在用户定义�c�d��和其他类型之间进行隐式�{换�?br />隐式转换可以通过消除不必要的�c�d��转换来提高源代码的可��L��?nbsp;但是�Q�因为隐式�{换不需要程序员��一�U�类型显式强制�{换�ؓ另一�U�类型，所以��用隐式�{换时必须格外��心�Q�以免出现意外结果�?nbsp;一般情况下�Q�隐式�{换运��符应当从不引发异常�q�且从不丢失信息�Q�以便可以在�E�序员不知晓的情况下安全使用它们�?nbsp;如果转换�q�算�W�不能满��那些条�Ӟ��则应��其标记�?nbsp;explicit�?nbsp;
class Digit
{
    public Digit(double d) { val = d; }
    public double val;
    // other members

    // User-defined conversion from Digit to double
    public static implicit operator double(Digit d)
    {
        return d.val;
    }
    //  User-defined conversion from double to Digit
    public static implicit operator Digit(double d)
    {
        return new Digit(d);
    }
}

class Program
{
    static void Main(string[] args)
    {
        Digit dig = new Digit(7);
        //This call invokes the implicit "double" operator
        double num = dig;
        //This call invokes the implicit "Digit" operator
        Digit dig2 = 12;
        Console.WriteLine("num = {0} dig2 = {1}", num, dig2.val);
        Console.ReadLine();
    }
}

天下 2016-06-17 14:06 发表评论

动态调用WebService(C#)

天下 — Fri, 17 Jun 2016 02:53:00 GMT

摘要: Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/-->动态调用WebService(C#)转自:http://www.cnblogs.com/xuwb/archive/2012/09/25/2701629.html通常我们在程序中需要调用WebService... 阅读全文

天下 2016-06-17 10:53 发表评论

WebService操作

天下 — Fri, 17 Jun 2016 02:33:00 GMT

WebService操作
转自:
http://blog.csdn.net/hi_kong/article/details/46356801

http://www.cnblogs.com/wayne-ivan/archive/2014/07/14/3842341.html

一、服务器端：
在VS2010中新建项目，首先选择.net framework2.0�Q�然后再选择web服务应用�E�序。如图所�C�：
然后在Service.cs文�g中添加自��q��Ҏ(gu��)��卛_��?br />二、C#winform调用webservice服务

新徏C#winfrom工程�Q�右键引�?/span>-》添加服务引�?/span>-》高�U?/span>-》添加web引用�Q�在URL后添加需要连接的url�Q�运行上面web服务�E�序��览器中��׃��出现�q�接的url�Q�，然后点击后面的箭��_��再点��d��引用卛_��?br />假设引用的服务名为WebReference�Q�类名称为Service�Q?br />using System.Web.Services;
using System.Web.Services.Description;
在代码中如下操作�Q?br />
WebReference.Service1 helloWord = new WebReference.Service1();
helloWord .Url =WebUrl;//讄��url
helloWord.helloWord�Q�）;//调用webservice中的�Ҏ(gu��)��
�l�束�?br />

WebService处理大数据量数据
在通过WebService处理大数据量数据时出现如下错误：
soap fault: �q�行配置文�g中指定的扩展时出现异常�?nbsp;---> ��过了最大请求长度�?nbsp;
解决�Ҏ(gu��)��Q?br />因�ؓ上传的文件大于系�l�默认配�|�的��|��asp.net web service默认的请求长度是4M�?br />1、针对单个项目，只需修改Web.config��可以了�Q?br />修改配置可以在web.config中重新设�|�，如下�Q?

<configuration>
<system.web>
<httpRuntime maxRequestLength="1048576" executionTimeout="3600" />
system.web>
configuration>

天下 2016-06-17 10:33 发表评论

�_��版本WCF DEMO

天下 — Thu, 16 Jun 2016 01:46:00 GMT

using System;
using System.ServiceModel; //��d��System.ServiceModel引用
using System.ServiceModel.Channels;

namespace ConsoleApplication1
{
    [ServiceContract]
    public interface IHelloWCF
    {
        [OperationContract]
        void Say(string input);
    }
    public sealed class HelloService : IHelloWCF
    {
        public void Say(string input)
        {
            Console.WriteLine("Hello {0}", input);
        }
    }
    class Program
    {
        static void Main(string[] args)
        {
            Uri address = new Uri("http://127.0.0.1:8733/IHelloWCF");
            BasicHttpBinding binding = new BasicHttpBinding();
            ServiceHost svc = new ServiceHost(typeof(HelloService));
            svc.AddServiceEndpoint(typeof(IHelloWCF), binding, address);
            svc.Opened += delegate {
                Console.WriteLine("The HelloWCF receiving application is ready");
            };
            svc.Open();

            ChannelFactory<IHelloWCF> factory = new ChannelFactory<IHelloWCF>(binding,new EndpointAddress(address));
            IHelloWCF proxy = factory.CreateChannel();
            proxy.Say("张三");
            proxy.Say("李四");
            proxy.Say("王二��d��");

            Console.ReadLine();
            svc.Close();
        }
    }
}

天下 2016-06-16 09:46 发表评论

WCF元数据公布的2�U�方式：httpGetEnabled与mex

天下 — Wed, 15 Jun 2016 07:42:00 GMT

WCF元数据公布的2�U�方式：httpGetEnabled与mex
一、元数据即WSDL�Q�描�q�C��服务的细节，以便客户端��用�?br />二、必��Mؓ服务配置ServiceMetadata行�ؓ�Q�才能�ؓ其生成WSDL�Q�才能再使用httpGetEnabled或mex��其公布出去
三、这两种方式公布出去的WSDL无区别。但公布的方式有区别
1、httpGetEnabled=true�Q�类似的�q�有httpsGetEnabled=true
此方式通过在服务在的URL后加“?wsdl”的方式公布WSDL�Q�可直接通过HTTP讉K��得到�?br />
2、mex
此方式以一般的�l�结�Ҏ(gu��)��式公布，支持各种协议�Q�http、tcp、NamedPipe

天下 2016-06-15 15:42 发表评论

天下 — Mon, 13 Jun 2016 09:52:00 GMT

数据契约�Q�DataContract�Q?br />服务契约定义了远�E�访问对象和可供调用的方法，数据契约则是服务端和客户端之间要传送的自定义数据类型�?br />一旦声明一个类型�ؓDataContract�Q�那么该�c�d��可以被序列化在服务端和客户端之间传送，如下所�C��?br />     [DataContract]
     public class UserInfo
     {
          //….
     }
只有声明为DataContract的类型的对象可以被传送，且只有成员属性会被传递，成员�Ҏ(gu��)��不会被传递。WCF对声明�ؓDataContract的类型提供更加细节的控制�Q�可以把一个成员排除在序列化范围以外，也就是说�Q�客��L��E�序不会获得被排除在外的成员的�Q何信息，包括定义和数据。默认情况下�Q�所有的成员属性都被排除在外，因此需要把每一个要传送的成员声明为DataMember�Q�如下所�C��?br />    [DataContract]
    public class UserInfo
    {
        [DataMember]
        public string UserName
        {
            get;
            set;
        }
        [DataMember]
        public int Age
        {
            get;
            set;
        }
        [DataMember]
        public string Location
        {
            get;
            set;
        }
        public string Zodiac
        {
            get;
            set;
        }
}
上面�q�段代码把UserInfo�c�d��明�ؓDataContract�Q�将UserName、Age、Location�q?个属性声明�ؓDataMember�Q�数据成员）。Zodiac成员没有被声明�ؓDataMember�Q�因此在交换数据�Ӟ��不会传输Zodiac的�Q何信息�?br />DataContract也支持Name/Namespace属性，如同ServiceContract�Q�Name和Namespace可以自定义名�U�和命名�I�间�Q�客��L��用自定义的名�U�和命名�I�间对DataContract�c�d��q�行讉K��?br />声明为DataMember的成员也可以自定义客��L��可见的名�U�ͼ�例如�Q?br />[DataMember(Name="Name")]
public string UserName
{
     get;
     set;
}
[DataMember(Name="Age")]
public int UserAge
{
          get;
          set;
}
除了Name和Namespace以外�Q�DataMember�q�有以下参数�Q�它们的含义分别如下�?br />�Q?/span>1�Q�IsRequired�Q��gؓtrue�Ӟ��要求序列化引擎检查对象是否存在该��|��若无�Q�则会有异常抛出�?br />�Q?/span>2�Q�Order�Q�bool�c�d��|��gؓtrue�Ӟ��序列化和反序列化�q�程��会按成员定义的��序�q�行�Q�这对依赖于成员位置的反序列化过�E�无比重要�?br />�Q?/span>3�Q�EmitDefaultvalue�Q��ؓ成员属性设�|�一个默认倹{�?/span>

天下 2016-06-13 17:52 发表评论

char和wchar_t 转String^

天下 — Mon, 21 Dec 2015 11:07:00 GMT

#include "stdafx.h"
#include
#using
using namespace System;
using namespace System::Text;
using namespace System::Runtime::InteropServices;

#ifdef _MANAGED
#endif

void abc123()
{
    using namespace msclr::interop;
    const char* msg1 = "Test String to Marshal";
    const wchar_t* msg2= L"Good Luck Aaron";
    String^ aMsg = marshal_as(msg1);
    String^ uMsg = marshal_as(msg2);
    Console::WriteLine(aMsg);
    Console::WriteLine(uMsg);
}
#pragma unmanaged
int _tmain(int argc, _TCHAR* argv[])
{
    abc123();
    system("pause");
    return 0;
}
#pragma managed

天下 2015-12-21 19:07 发表评论

天下 — Mon, 21 Dec 2015 10:36:00 GMT

略谈GCHandle【�{�?br />http://blog.163.com/vk_01313/blog/static/17219228200912491729457/
我们在��用c#托管代码�Ӟ��内存地址和GC回收那不是我们关心的�Q�CLR已经�l�我们暗��操作�?br />但是如果我们在c#中调用了一个非托管代码�Q�比如vc的DLL,而且他有个回调函敎ͼ�需要引用c#中的某个对象�q�操作，
�q�时候你��得要小心了�?br />要是非托��代码中用到得托��代码那个对象被GC�l�回收了�Q�这时候就会报内存错误�?br />所以我们就要把那个对象“�?#8221;�?pin)�Q�让它的内存地址固定�Q�而不被垃圑֛�收掉�Q�然后最后我们自��q��理，自己释放内存,�q�时候就需要GCHandle,来看个msdn上的例子:

using System.Runtime.InteropServices;

namespace ConsoleApplication1
{

    //C#
    public delegate bool CallBack(int handle, IntPtr param);
    public class LibWrap
    {
        [DllImport("user32.dll")]
        public static extern bool EnumWindows(CallBack cb, IntPtr param);
    }

    class Program
    {
        static void Main(string[] args)
        {
            TextWriter tw = System.Console.Out;
            GCHandle gch = GCHandle.Alloc(tw);
            CallBack cewp = new CallBack(CaptureEnumWindowsProc);
            LibWrap.EnumWindows(cewp, (IntPtr)gch);
            gch.Free();
            Console.Read();

        }
        private static bool CaptureEnumWindowsProc(int handle, IntPtr param)
        {
            GCHandle gch = (GCHandle)param;
            TextWriter tw = (TextWriter)gch.Target;
            tw.WriteLine(handle);
            return true;
        }

    }
}

对上面的代码�Q�略加解释：gch 会钉�?pin)tw�q�个对象�Q��其不受GC��理�Q�告诉它�Q�以后你崩管我，我也不用�l�你上税,其实��理权已�l�给gch�Q�通过free来释攑ֆ�存�?br />�q�种情况主要用在托管和非托管代码交互的时候，防止内存泄露来��用GCHandle�?/div>

天下 2015-12-21 18:36 发表评论

pin_ptr �?interior_ptr

天下 — Mon, 21 Dec 2015 09:11:00 GMT

CLR语法中，值类型指针分��Z��U�类型：V*�Q�限于非 CLR 堆位�|�）和内部指�?nbsp;interior_ptr�Q�允�怽�不要求托��堆内的地址�Q��?br />

钉住指针
通常�Q�在压羃阶段�Q�垃圑֛�收器可选择��驻留在 CLR 堆上的对象移动到堆内的不同位�|�。这�U�移动对于跟�t�句柄、跟�t�引用和内部指针而言不是问题�Q�它们都透明地更新这些实体。但是，如果用户在运行时环境外传递了 CLR 堆上对象的地址�Q�这�U�移动就会导致问题。在�q�种情况下，对象的不�E�_��q�动可能��D��q�行时失败。要避免此类对象的移动，必须在本地将它们钉在自己的位�|�上以供外部使用�?br />
在托��扩展中�Q?#8220;钉住指针”是通过使用 __pin 关键字限定指针声明来声明的。下面是一个来自托��扩展规范的�l�过略微修改的示例：

  复制代码
__gc struct H { int j; };

int main()
{
   H * h = new H;
   int __pin * k = & h -> j;

   // …
};

在新的语�a�设计中，钉住指针是��用类��g��内部指针的语法来声明的�?br />
  复制代码
ref struct H
{
public:
   int j;
};

int main()
{
   H^ h = gcnew H;
   pin_ptr<int> k = &h->j;

   // …
}

interior_ptr
Declares a pointer to inside a reference type, but not to the object itself. An interior pointer can point to a reference handle, value type, boxed type handle, member of a managed type, or to an element of a managed array.
cli::interior_ptr var = &initializer;

Remarks
A native pointer is not able to track an item as its location changes on the managed heap, which results from the garbage collector moving instances of an object. In order for a pointer to correctly refer to the instance, the runtime needs to update the pointer to the newly positioned object.

An interior_ptr represents a superset of the functionality of a native pointer. Therefore, anything that can be assigned to a native pointer can also be assigned to an interior_ptr. An interior pointer is permitted to perform the same set of operations as native pointers, including comparison and pointer arithmetic.

An interior pointer can only be declared on the stack. An interior pointer cannot be declared as a member of a class.

Since interior pointers exist only on the stack, taking the address of an interior pointer yields an unmanaged pointer.

interior_ptr has an implicit conversion to bool, which allows for its use in conditional statements.

For information on how to declare an interior pointer that points into an object that cannot be moved on the garbage-collected heap, see pin_ptr.

interior_ptr is in the cli namespace. See cli Namespace for more information.

//Example
// interior_ptr.cpp
// compile with: /clr
using namespace System;

ref class MyClass {
public:
   int data;
};

int main() {
   MyClass ^ h_MyClass = gcnew MyClass;
   h_MyClass->data = 1;
   Console::WriteLine(h_MyClass->data);

   interior_ptr<int> p = &(h_MyClass->data);
   *p = 2;
   Console::WriteLine(h_MyClass->data);

   // alternatively
   interior_ptr p2 = &h_MyClass;
   (*p2)->data = 3;
   Console::WriteLine((*p2)->data);
}

天下 2015-12-21 17:11 发表评论

天下 — Mon, 21 Dec 2015 08:27:00 GMT

StructLayout�Ҏ(gu��)�?br />
     公共语言�q�行库利用StructLayoutAttribute控制�c�L��l�构的数据字�D�在托管内存中的物理布局,即类或结构需要按某种方式排列。如果要��类传递给需要指定布局的非托管代码�Q�则昑ּ�控制�c�d��局是重要的。它的构造函��C��?nbsp;LayoutKind值初始化 StructLayoutAttribute �cȝ��新实例�?nbsp;LayoutKind.Sequential 用于强制��成员按其出现的��序�q�行��序布局�?br />
  StructLayout�Ҏ(gu��)��允许我们控制Structure语句块的元素在内存中的排列方�?以及当这些元素被传递给外部DLL�Ӟ��q�行库排列这些元素的方式。Visual   Basic�l�构的成员在内存中的��序是按照它们出现在源代码中的顺序排列的�Q�尽��编译器可以自由的插入填充字节来安排�q�些成员�Q�以便��?6位数值用子边界对齐，32位数值用双字边界寚w��?nbsp;

  使用�q�种排列�Q�未压羃布局�Q�提供的性能最佟�?nbsp;

通过System.Runtime.InteropServices.StructLayout   �Ҏ(gu��)��精��的控制每一个结构成员的位置�?br />System.Runtime.InteropServices.StructLayout   允许的值有:
StructLayout.Auto
StructLayout.Sequential
StructLayout.Explicit

1.Sequential,��序布局,比如
struct S1
{
  int a;
  int b;
}
那么默认情况下在内存里是先排a,再排b
也就是如果能取到a的地址,和b的地址,则相差一个int�c�d��的长�?4字节
[StructLayout(LayoutKind.Sequential)]
struct S1
{
  int a;
  int b;
}
�q�样和上一个是一��L��.因�ؓ默认的内存排列就是Sequential,也就是按成员的先后顺序排�?
2.Explicit,�_��布局
需要用FieldOffset()讄��每个成员的位�|?br />�q�样��可以实现类似c的公用体(union)的功�?br />[StructLayout(LayoutKind.Explicit)]
struct S1
{
    [FieldOffset(0)] int a;
    [FieldOffset(0)] int b;
}
�q�样a和b在内存中地址相同

  StructLayout�Ҏ(gu��)��支持三�U�附加字�D�：CharSet、Pack、Size�?nbsp;
·   CharSet定义在结构中的字�W�串成员在结构被传给DLL时的排列方式。可以是Unicode、Ansi或Auto�?nbsp;
  默认为Auto�Q�在WIN   NT/2000/XP中表�C�字�W�串按照Unicode字符串进行排列，在WIN   95/98/Me中则表示按照ANSI字符串进行排列�?nbsp;
·   Pack定义了结构的��装大小。可以是1�?�?�?�?6�?2�?4�?28或特�D��?。特�D��?表示当前操作�q�_��默认的压�~�大��?nbsp;

  [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
    public struct LIST_OPEN
    {
        public int dwServerId;
        public int dwListId;
        public System.UInt16 wRecordSize;
        public System.UInt16 wDummy;
        public int dwFileSize;
        public int dwTotalRecs;
        public NS_PREFETCHLIST sPrefetch;
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 24)] public string szSrcMach;
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 24)] public string szSrcComp;
    }

此例中用到MashalAs�Ҏ(gu��)��，它用于描�q�字�D�c��方法或参数的封送处理格式。用它作为参数前�~��q�指定目标需要的数据�c�d��?br />例如�Q�以下代码将两个参数作�ؓ数据�c�d��长指针封送给 Windows API 函数的字�W�串 (LPStr)�Q?nbsp;
[MarshalAs(UnmanagedType.LPStr)] String existingfile;

[MarshalAs(UnmanagedType.LPStr)] String newfile;

注意�l�构作�ؓ参数时候，一般前面要加上ref修饰�W�，否则会出现错误：对象的引用没有指定对象的实例�?br />[ DllImport( "kernel32", EntryPoint="GetVersionEx" )]
public static extern bool GetVersionEx2( ref OSVersionInfo2 osvi );

string result;
IntPtr strPtr = new IntPtr() ;// unmanaged api TestStringAsResultIntPrt(1);
result = Marshal.PtrToStringUni(strPtr);
result = Marshal.PtrToStringAnsi(strPtr);
Marshal.FreeCoTaskMem(strPtr);

天下 2015-12-21 16:27 发表评论

如何�Q�将 System::String 转换为标准字�W�串

天下 — Mon, 14 Dec 2015 07:46:00 GMT

//《精�?NET互操作：P/Invoke、C++ Interop和COM Interop�?br />//ms-help://MS.VSCC.v90/MS.MSDNQTR.v90.chs/dv_vccore/html/79e2537e-d4eb-459f-9506-0e738045b59e.htm
// convert_system_string.cpp
// compile with: /clr
#include <string>
#include
using namespace std;
using namespace System;

void MarshalString ( String ^ s, string& os ) {
   using namespace Runtime::InteropServices;
   const char* chars =
      (const char*)(Marshal::StringToHGlobalAnsi(s)).ToPointer();
   os = chars;
   Marshal::FreeHGlobal(IntPtr((void*)chars));
}

void MarshalString ( String ^ s, wstring& os ) {
   using namespace Runtime::InteropServices;
   const wchar_t* chars =
      (const wchar_t*)(Marshal::StringToHGlobalUni(s)).ToPointer();
   os = chars;
   Marshal::FreeHGlobal(IntPtr((void*)chars));
}

int main() {
   string a = "test";
   wstring b = L"test2";
   String ^ c = gcnew String("abcd");

   cout << a << endl;
   MarshalString(c, a);
   c = "efgh";
   MarshalString(c, b);
   cout << a << endl;
   wcout << b << endl;
}

天下 2015-12-14 15:46 发表评论

C++的dll调用C#的dll

天下 — Mon, 07 Dec 2015 12:23:00 GMT

C++的dll调用C#的dll
1�Q�用C#写�Q何的�c�d��Q�如�Q�NeoWayMesCommon.dll
2�Q�C++的dll中要引用此类库，注意不能在stdafx.h中引用，最后是在cpp文�g中引用�?br />#using
#using "../Debug/NeoWayMesCommon.dll" //引用此类�?/span>
using namespace NeoWayMes;
using namespace System;
3) C++ �~�译讄��一定设�|��ؓ�Q�支持公��p��a��q�行时支�?/clr)
4) 必须��C#的dll拯��至VC工程�q�行的目录，否则报异帔R��误�?br />5) 其他的参见c++/cli语法标准

天下 2015-12-07 20:23 发表评论

Double Thunking

天下 — Tue, 01 Dec 2015 03:14:00 GMT

By default, when compiling with /clr (not /clr:pure), the definition of a managed function causes the compiler to generate a managed entry point and a native

entry point. This allows the managed function to be called from native and managed call sites. However, when a native entry point exists, it can be the entry

point for all calls to the function. If a calling function is managed, the native entry point will then call the managed entry point. In effect, two calls

are required to invoke the function (hence, double thunking). For example, virtual functions are always called through a native entry point.

One resolution is to tell the compiler not to generate a native entry point for a managed function, that the function will only be called from a managed

context, by using the __clrcall calling convention.

Similarly, if you export (dllexport, dllimport) a managed function, a native entry point is generated and any function that imports and calls that function

will call through the native entry point. To avoid double thunking in this situation, do not use native export/import semantics; simply reference the

metadata via #using (see The #using Directive).

In Visual C++ 2005 the compiler was updated to reduce unnecessary double thunking. For example, any function with a managed type in the signature (including

return type) will implicitly be marked as __clrcall. For more information on double thunk elimination, see

http://msdn.microsoft.com/msdnmag/issues/05/01/COptimizations/default.aspx.

Example

The following sample demonstrates double thunking. When compiled native (without /clr), the call to the virtual function in main generates one call to T's

copy constructor and one call to the destructor. Similar behavior is achieved when the virtual function is declared with /clr and __clrcall. However, when

just compiled with /clr, the function call generates a call to the copy constructor but there is another call to the copy constructor due to the

native-to-managed thunk.

�U?MSIL �E�序集可以调用非托管函数�Q�但不能由非托管函数调用。因此，与非托管函数使用的服务器代码相比�Q�纯 MSIL 更适合于��用非托管函数的客��L��代码�?/div>

当我们��?clr选项�Q�不�?clr:pure�Q�进行编译的时候，一个托��函�?managed function)�Q�会��D��~�译器生成一个托��的入口�?managed entry point)和一个原生的入口�?/div>

(native entry point)�Q�这样可以��得托��函数既可以被托��代码调用，也可以被原生代码调用。但是，当一个原生的入口点存在的时候，它将成�ؓ所有调用的入口炏V��也��是�?/div>

如果调用者是托管的，它还是会先去调用原生入口点，然后原生的入口点再去调用托管的入口点�Q�这��意味着调用了两�ơ函数入口点�Q�Double Thunking�Q��?nbsp;

c++ cli 标准

天下 2015-12-01 11:14 发表评论

天下 — Tue, 01 Dec 2015 03:09:00 GMT

// MarshalANSI1.cpp
// compile with: /clr
#include
#include

using namespace std;
using namespace System;
using namespace System::Runtime::InteropServices;

#pragma unmanaged

void NativeTakesAString(const char* p) {
   printf_s("(native) received '%s'\n", p);
}

#pragma managed

int main() {
   String^ s = gcnew String("sample string");
   IntPtr ip = Marshal::StringToHGlobalAnsi(s);
   const char* str = static_cast<const char*>(ip.ToPointer());

   Console::WriteLine("(managed) passing string");
   NativeTakesAString( str );

   Marshal::FreeHGlobal( ip );
}

下面的示例演�C��问由非托��函数调用的托管函数中的 ANSI 字符串所需的数据封送处理。托��函数在接收到本机字�W�串�Ӟ��可以直接使用该字�W�串�Q�也可以按所�C�方式��?nbsp;PtrToStringAnsi �Ҏ(gu��)��其转换为托��字�W�串�?br />
  复制代码
// MarshalANSI2.cpp
// compile with: /clr
#include
#include

using namespace std;

using namespace System;
using namespace System::Runtime::InteropServices;

#pragma managed

void ManagedStringFunc(char* s) {
   String^ ms = Marshal::PtrToStringAnsi(static_cast(s));
   Console::WriteLine("(managed): received '{0}'", ms);
}

#pragma unmanaged

void NativeProvidesAString() {
   cout << "(native) calling managed func\n";
   ManagedStringFunc("test string");
}

#pragma managed

int main() {
   NativeProvidesAString();
}

天下 2015-12-01 11:09 发表评论

如何�Q�将 System::String 转换�?wchar_t* �?char*

天下 — Tue, 01 Dec 2015 03:08:00 GMT

ms-help://MS.VSCC.v90/MS.MSDNQTR.v90.chs/dv_vccore/html/385da01b-5649-4543-8076-e3e251243ff0.htm

// convert_string_to_wchar.cpp
// compile with: /clr
#include < stdio.h >
#include < stdlib.h >
#include < vcclr.h >

using namespace System;

int main() {
   String ^str = "Hello";

   // Pin memory so GC can't move it while native function is called
   pin_ptr<const wchar_t> wch = PtrToStringChars(str);
   printf_s("%S\n", wch);

   // Conversion to char* :
   // Can just convert wchar_t* to char* using one of the
   // conversion functions such as:
   // WideCharToMultiByte()
   // wcstombs_s()
   //  etc
   size_t convertedChars = 0;
   size_t  sizeInBytes = ((str->Length + 1) * 2);
   errno_t err = 0;
   char    *ch = (char *)malloc(sizeInBytes);

   err = wcstombs_s(&convertedChars,
                    ch, sizeInBytes,
                    wch, sizeInBytes);
   if (err != 0)
      printf_s("wcstombs_s  failed!\n");

    printf_s("%s\n", ch);
}

天下 2015-12-01 11:08 发表评论

C# using 三种使用方式

天下 — Tue, 10 Nov 2015 02:45:00 GMT

C# using 三种使用方式
1.using指��o�?span style="color: #0000FF; ">using + 命名�I�间名字�Q�这样可以在�E�序中直接用命��o�I�间中的�c�d��Q�而不必指定类型的详细命名�I�间�Q�类��g��Java的import�Q�这个功能也是最常用的，几乎每个cs的程序都会用到�?nbsp;
例如�Q?span style="color: #0000FF; ">using System; 一般都会出现在*.cs中�?br />
2.using别名�?span style="color: #0000FF; ">using + 别名 = 包括详细命名�I�间信息的具体的�c�d��?nbsp;
�q�种做法有个好处��是当同一个cs引用了两个不同的命名�I�间�Q�但两个命名�I�间都包括了一个相同名字的�c�d��的时候。当需要用到这个类型的时候，��每个地斚w��要用详细命名�I�间的办法来区分�q�些相同名字的类型。而用别名的方法会更简�z�，用到哪个�c�d��l�哪个类做别名声明就可以了。注意：�q�不是说两个名字重复�Q�给其中一个用了别名，另外一个就不需要用别名了，如果两个都要使用�Q�则两个都需要用using来定义别名的�?br />using Row = Newtonsoft.Json.Linq.JObject;
using Rows = Newtonsoft.Json.Linq.JArray;

3.using语句�Q�定义一个范��_��在范围结束时处理对象�?nbsp;
场景�Q?nbsp;
当在某个代码�D�中使用了类的实例，而希望无论因��Z��么原因，只要��d��了这个代码段��p��动调用这个类实例的Dispose�?nbsp;
要达到这��L��目的�Q�用trycatch来捕捉异�怹�是可以的�Q�但用using也很方便�?br />
using (Class1 cls1 = new Class1(), cls2 = new Class1())
{
// the code using cls1, cls2
} // call

天下 2015-11-10 10:45 发表评论

天下 — Thu, 30 Jul 2015 11:59:00 GMT

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using MySql.Data.MySqlClient;
using System.Xml;
using Row = System.Collections.Generic.Dictionary<string, string>;

namespace NeowayFixPlatform
{

    class MysqlFunction
    {
        public static string table_fix = "nw_fix_record";

        public bool IsConnected()
        {
            return (mysql.State == ConnectionState.Open);
        }
        public MysqlFunction()
        {
            if (mysql.State != ConnectionState.Open)
                mysql.Open();
        }

        ~MysqlFunction()
        {
            if (mysql.State == ConnectionState.Open)
                mysql.Dispose();
        }
        private static String mysqlcon = GetConfigString();
        MySqlConnection mysql = new MySqlConnection(mysqlcon);

        public string quote(ref string value)
        {
            value = value.Replace(@"\", @"\\").Replace("'", @"\'");
            return value;
        }
        public StringBuilder quote(ref StringBuilder value)
        {
            value = value.Replace(@"\", @"\\").Replace("'", @"\'");
            return value;
        }

        public StringBuilder GetPairSQLString(Row row)
        {
            StringBuilder strSQL = new StringBuilder();

            foreach (KeyValuePair<string, string> pair in row)
            {
                string value = pair.Value.ToString();
                this.quote(ref value);
                strSQL.AppendFormat("{0}='{1}',", pair.Key, value);
            }
            strSQL.Remove(strSQL.Length-1, 1);
            return strSQL;
        }

        public bool UpdateOne(string table,Row row,string format,params object[] args)
        {
            StringBuilder condition = new StringBuilder();
            condition.AppendFormat(format, args);
            return this.UpdateOne(table, row, condition.ToString());
        }

        public bool UpdateOne(string strTable, Row row, string strQuery)
        {
            StringBuilder strSQL = new StringBuilder();
            try
            {
                strSQL.AppendFormat("UPDATE {0} set {1} WHERE {2} LIMIT 1", strTable, GetPairSQLString(row), strQuery);
                //mysql.Open();
                MySqlCommand cmd = new MySqlCommand(strSQL.ToString(), mysql);
                cmd.ExecuteNonQuery();
                cmd.Dispose();
                return true;
            }
            catch (System.Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
            return false;
        }


        public Row FetchOne(string strSQL)
        {
            Row row = new Row();
            try
            {

                //mysql.Open();
                MySqlCommand cmd = new MySqlCommand(strSQL.ToString(),mysql);
                MySqlDataReader reader = cmd.ExecuteReader();
                reader.Read();
                for (int i = 0; i < reader.FieldCount; i++)
                {
                    if (reader.HasRows)
                        row[reader.GetName(i)] = reader[i].ToString();
                }
                reader.Close();
                cmd.Dispose();
            }
            catch (System.Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
            return row;
        }

        #region 获取登陆字符
        ///

/// 获取登陆字符
///

        ///
        public static string GetConfigString()
        {
            string spath = Application.StartupPath;
            spath += "\\config.xml";
            XmlDocument xml = new XmlDocument();
            xml.Load(spath);
            XmlNode config = xml.SelectSingleNode("config");
            XmlNode dbname = config.SelectSingleNode("dbname");
            XmlNode ipaddr = config.SelectSingleNode("ipaddr");
            XmlNode username = config.SelectSingleNode("username");
            XmlNode password = config.SelectSingleNode("password");

            return string.Format("database={0};Password={1};User ID={2};server={3}", dbname.InnerText, password.InnerText, username.InnerText, ipaddr.InnerText);

        }
        #endregion

        public bool BindData(string sql,ref DataGridView dgv)
        {
            DataSet dataset = new DataSet();
            DataTable datatable = new DataTable();
            try
            {
                MySqlDataAdapter mdap = new MySqlDataAdapter(sql, mysql);
                mdap.Fill(dataset);
                datatable = dataset.Tables[0];
                dgv.DataSource = datatable;
                return true;
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
            return false;
        }

        #region 用户��d��
        ///

/// �pȝ��d��
///

        ///
        public bool Login(cUserInfo userinfo)
        {
            DataSet dataset = new DataSet();
            DataTable datatable = new DataTable();
            try
            {
                //MySqlDataAdapter 数据库执行函敎ͼ�查询�Q�插入，删除都可使用
               MySqlDataAdapter mdap = new MySqlDataAdapter("select * from nw_user where user_name = '" + userinfo.User_name + "' and user_pwd = '" + userinfo.User_password + "'", mysql);
               mdap.Fill(dataset);
               datatable = dataset.Tables[0];

            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }

            if (datatable.Rows.Count == 1)
            {
                DataRow datarow = datatable.Rows[0];
                userinfo.User_power = datarow["user_power"].ToString();
                return true;
            }
            return false;

        }
        #endregion

        public bool SaveFix(Dictionary<string,string> row,bool bNew)
        {
            StringBuilder strSQL = new StringBuilder();
            try
            {
                if (bNew)
                    strSQL.Append("INSERT INTO nw_fix_record set ");
                else
                    strSQL.Append("UPDATE nw_fix_record set ");
                strSQL.AppendFormat("{0}",GetPairSQLString(row));

                if (!bNew)
                {
                    strSQL.AppendFormat(" WHERE IMEI_MEID='{0}' limit 1", row["IMEI_MEID"]);
                }
                //mysql.Open();

                MySqlCommand cmd = new MySqlCommand(strSQL.ToString(), mysql);
                cmd.ExecuteNonQuery();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                return false;
            }
            return true;
        }

        #region 获取所有��品型�?br />        ///

/// 获取所有��品型�?br /> ///

        ///
        public string[] GetProducts()
        {
            DataSet dataset = new DataSet();
            DataTable datatable = new DataTable();
            string[] rows = null;
            try
            {

                MySqlDataAdapter mdap = new MySqlDataAdapter("select * from nw_product where 1", mysql);
                mdap.Fill(dataset);
                datatable = dataset.Tables[0];

            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                return rows;
            }

            int row_count = datatable.Rows.Count;
            if (row_count>0)
            {
                rows = new string[row_count];
                for (int i = 0; i < row_count; i++ )
                {
                    rows[i] = datatable.Rows[i][0].ToString();
                }
            }
            return rows;
        }
        #endregion

        #region 获取所有客户名�U?br />        ///

/// 获取所有客户名�U?br /> ///

        ///
        public string[] GetAllClientName()
        {
            DataSet dataset = new DataSet();
            DataTable datatable = new DataTable();
            string[] rows = null;
            try
            {

                MySqlDataAdapter mdap = new MySqlDataAdapter("select client_name from nw_client where 1", mysql);
                mdap.Fill(dataset);
                datatable = dataset.Tables[0];

            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                return rows;
            }

            int row_count = datatable.Rows.Count;
            if (row_count > 0)
            {
                rows = new string[row_count];
                for (int i = 0; i < row_count; i++)
                {
                    rows[i] = datatable.Rows[i][0].ToString();
                }
            }
            return rows;
        }
        #endregion

        #region 获取所有维修�h�?br />        ///

/// 获取所有维修�h�?br /> ///

        ///
        public string[] GetAllRepairEr()
        {
            DataSet dataset = new DataSet();
            DataTable datatable = new DataTable();
            string[] rows = null;
            try
            {

                MySqlDataAdapter mdap = new MySqlDataAdapter("select user_name from nw_user where user_power='�l�修�? order by user_id", mysql);
                mdap.Fill(dataset);
                datatable = dataset.Tables[0];

            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
                return rows;
            }

            int row_count = datatable.Rows.Count;
            if (row_count > 0)
            {
                rows = new string[row_count];
                for (int i = 0; i < row_count; i++)
                {
                    rows[i] = datatable.Rows[i][0].ToString();
                }
            }
            return rows;
        }

    }
    #endregion

    #region 定义用户�?br />    public class cUserInfo
        {
            private int user_id;

            public int User_id
            {
                get { return user_id; }
                set { user_id = value; }
            }

            private string user_name;

            public string User_name
            {
                get { return user_name; }
                set { user_name = value; }
            }
            private string user_password;

            public string User_password
            {
                get { return user_password; }
                set { user_password = value; }
            }
            private string user_power;

            public string User_power
            {
                get { return user_power; }
                set { user_power = value; }
            }
        }
   #endregion

}

天下 2015-07-30 19:59 发表评论

杂记Json,MySQL,C#

天下 — Mon, 06 Jul 2015 11:37:00 GMT

MySQL 1045权限错误的解�?
GRANT ALL PRIVILEGES ON *.* TO test_user@'%' IDENTIFIED BY '123456' WITH GRANT OPTION;

libJson(Jsoncpp),够用�?
C++:
extern "C" LIB_MESCLIENT_API int nw_save_prodmade_data(const char* jo_in);

Json::Value jo;
jo["row"]["product_id"] = "21265";
jo["row"]["product_sn"] = 223456789012345678;
int error_code = nw_save_prodmade_data(jo.toStyledString().c_str());

C#下用Newtonsoft.Json也挺好用�?br />using Newtonsoft.Json.Linq;
JObject jo = new JObject();
jo["row"] = new JObject();
//此部分在dll内部会插入到可追溯状态表 nw_sn_status
jo["row"]["product_id"] = "12\r\n3\"12'\"65"; //产品ID
StringBuilder row = new StringBuilder(jo.ToString());
int error_code = nw_save_prodmade_data(row);

天下 2015-07-06 19:37 发表评论

C#中结构体与字节流互相转换

天下 — Thu, 20 Sep 2012 03:37:00 GMT

一、c#�l�构�?br />
1、定义与C++对应的C#�l�构�?br />
在c#中的�l�构体不能定义指针，不能定义字符数组�Q�只能在里面定义字符数组的引用�?br />C++的消息结构体如下�Q?br />//消息格式 4+16+4+4= 28个字�?/span>
struct cs_message{
         u32_t        cmd_type;
         char username[16];
         u32_t        dstID;
         u32_t        srcID;
};
C#定义的结构体如下:
[StructLayout(LayoutKind.Sequential, Pack = 1)]
    public struct my_message
    {
        public UInt32  cmd_type;
        [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 16)]
        public string username;
        public UInt32  dstID;
        public UInt32  srcID;
        public my_message(string s)
        {
            cmd_type = 0;
            username = s;
            dstID = 0;
            srcID = 0;
        }
}
在C++的头文�g定义中，使用�?nbsp;#pragma pack 1 字节�?寚w��Q�所以C#的结构体也必��要加上对应的特性，LayoutKind.Sequential属性让�l�构体在导出到非托管内存时按出现的顺序依�ơ布局,而对于C++的char数组�c�d��Q�C#中可以直接��用string来对应，当然了，也要加上��送的�Ҏ(gu��)��和长度限制�?br />2、结构体与byte[]的互相�{�?br />
定义一个类�Q�里面有2个方法去实现互�{�Q?br />public class Converter
{
        public Byte[] StructToBytes(Object structure)
        {
            Int32 size = Marshal.SizeOf(structure);
            Console.WriteLine(size);
            IntPtr buffer = Marshal.AllocHGlobal(size);
            try
            {
                Marshal.StructureToPtr(structure, buffer, false);
                Byte[] bytes = new Byte[size];
                Marshal.Copy(buffer, bytes, 0, size);
                return bytes;
            }
            finally
            {
                Marshal.FreeHGlobal(buffer);
            }
        }
        public Object BytesToStruct(Byte[] bytes, Type strcutType)
        {
            Int32 size = Marshal.SizeOf(strcutType);
            IntPtr buffer = Marshal.AllocHGlobal(size);
            try
            {
                Marshal.Copy(bytes, 0, buffer, size);
                return Marshal.PtrToStructure(buffer, strcutType);
            }
            finally
            {
                Marshal.FreeHGlobal(buffer);
            }
        }
}
3、测试结果：

static void Main(string[] args)
{
    //定义转换�cȝ��一个对象�ƈ初始�?/span>
Converter Convert = new Converter();
//定义消息�l�构�?/span>
    my_message m;

    //初始化消息结构体
    m = new my_message("yanlina");
    m.cmd_type = 1633837924;
    m.srcID = 1633837924;
m.dstID = 1633837924;

//使用转换�cȝ��对象的StructToBytes�Ҏ(gu��)��把m�l�构体�{换成Byte
Byte[] message = Convert.StructToBytes(m);
//使用转换�cȝ��对象的BytesToStruct�Ҏ(gu��)��把Byte转换成m�l�构�?/span>
my_message n = (my_message)Convert.BytesToStruct(message, m.GetType());
//输出��试
    Console.WriteLine(Encoding.ASCII.GetString(message));
    Console.WriteLine(n.username);
}
�l�构体的size�?8个字节和c++的结构体一��P��同时可以��结构体和字节数�l�互转，方便UDP的发送和接收�?/span>

转自:http://blog.csdn.net/huxiangyang4/article/details/5853247

天下 2012-09-20 11:37 发表评论

C#委派Delegate

天下 — Thu, 07 Jun 2012 08:41:00 GMT

//直接上MSDN上的C#代码:
using System;
public class SamplesDelegate
{

    // Declares a delegate for a method that takes in an int and returns a String.
    public delegate String myMethodDelegate(int myInt);

    // Defines some methods to which the delegate can point.
    public class mySampleClass
    {

        // Defines an instance method.
        public String myStringMethod(int myInt)
        {
            if (myInt > 0)
                return ("positive");
            if (myInt < 0)
                return ("negative");
            return ("zero");
        }

        // Defines a static method.
        public static String mySignMethod(int myInt)
        {
            if (myInt > 0)
                return ("+");
            if (myInt < 0)
                return ("-");
            return ("");
        }
    }

    public static void Main()
    {

        // Creates one delegate for each method. For the instance method, an
        // instance (mySC) must be supplied. For the static method, use the
        // class name.
        mySampleClass mySC = new mySampleClass();
        myMethodDelegate myD1 = new myMethodDelegate(mySC.myStringMethod);
        myMethodDelegate myD2 = new myMethodDelegate(mySampleClass.mySignMethod);

        // Invokes the delegates.
        Console.WriteLine("{0} is {1}; use the sign \"{2}\".", 5, myD1(5), myD2(5));
        Console.WriteLine("{0} is {1}; use the sign \"{2}\".", -3, myD1(-3), myD2(-3));
        Console.WriteLine("{0} is {1}; use the sign \"{2}\".", 0, myD1(0), myD2(0));
    }

}

// d11.cpp : Defines the entry point for the console application.
//C++代码

#include "stdafx.h"
#include <iostream>
#include <string>

using namespace std;

typedef string myMethodDelegate(int myInt);

string myStringMethod ( int myInt )  {
    if ( myInt > 0 )
        return string( "positive" );
    if ( myInt < 0 )
        return string( "negative" );
    return string( "zero" );
}

string mySignMethod ( int myInt )  {
    if ( myInt > 0 )
        return string( "+" );
    if ( myInt < 0 )
        return string( "-" );
    return  string( "" );
}

int _tmain(int argc, _TCHAR* argv[])
{
    myMethodDelegate* myD1 = myStringMethod;
    myMethodDelegate* myD2 = mySignMethod;

    // Invokes the delegates.
    printf( "{%d} is {%s}; use the sign \"{%s}\". \r\n", 5, myD1( 5 ).c_str(), myD2( 5 ).c_str() );
    printf( "{%d} is {%s}; use the sign \"{%s}\". \r\n", -3, myD1( -3 ).c_str(), myD2( -3 ).c_str() );
    printf( "{%d} is {%s}; use the sign \"{%s}\".\r\n", 0, myD1( 0 ).c_str(), myD2( 0 ).c_str() );
    return 0;
}

天下 2012-06-07 16:41 发表评论