1. 方法定义

[DllImport("wininet.dll")]

private extern static bool InternetGetConnectedState( out int connectionDescription, int reservedValue ) ;

2. 方法说明

参数:

connectionDescription : 连接说明

reservedValue : 保留值

返回值:

true: On Line

false: Off Line

3. 调用方法

a. 你必须在你的code里引用System.Runtime.InteropServices,否则,会有编译错误

b. 定义一个变量 int I = 0;

c. 调用bool state = InternetGetConnectedState(out I,0);



完整的代码:

using System.Runtime.InteropServices;



namespace internet

{

public class Class1

{

[DllImport("wininet.dll")]

private extern static bool InternetGetConnectedState( out int connectionDescription, int reservedValue ) ;

public Class1(){}



private bool IsConnected()

{

int I=0;

bool state = InternetGetConnectedState(out I,0);

return state;

}

}

}