C#如何使用API函数？

Question

C#如何使用API函数？

Answer 1

        [DllImport("user32.dll")]
        static extern int GetClassName(
            IntPtr hWnd,
            StringBuilder lpClassName,
            int nMaxCount
            );

Answer 2

platform invoke参考:
Platform Invoke Tutorial
http://msdn.microsoft.com/en-us/library/aa288468.aspxSample Code:
using System.Runtime.InteropServices;
1。 [DllImport("user32.dll")]
    public static extern int MessageBox(int hWnd, String text, 
                                       String caption, uint type);2. using System.Runtime.InteropServices;[StructLayout(LayoutKind.Sequential)]
public struct Point {
    public int x;
    public int y;
}   [StructLayout(LayoutKind.Explicit)]
public struct Rect {
    [FieldOffset(0)] public int left;
    [FieldOffset(4)] public int top;
    [FieldOffset(8)] public int right;
    [FieldOffset(12)] public int bottom;
}   class Win32API {
    [DllImport("User32.dll")]
    public static extern bool PtInRect(ref Rect r, Point p);

Answer 3

using System.Runtime.InteropServices; 
[DllImport("user32.dll")]
public static extern ReturnType FunctionName(type arg1,type arg2,...);
http://www.cnblogs.com/cdo/archive/2005/08/05/208128.html