获得应用程序的图标(c#描述)

需要调用api完成
声明:
VB.NET版本
Private   Declare   Auto   Function   SHGetFileInfo   _  
          Lib   "shell32"   (ByVal   pszPath   As   String,   ByVal   dwFileAttributes   As   Integer,   ByRef   psfi   As   SHFILEINFO,   _  
          ByVal   cbFileInfo   As   Integer,   ByVal   uFlags   As   Integer)   As   Integer
C#中建立了一个类(原方法来自网友)
GetAppIconApi

 1using System;
 2using System.Reflection;
 3using System.Runtime.InteropServices;
 4namespace GetAppIcon
 5{
 6    public class GetAppIconApi
 7    {
 8        public struct SHFileInfo
 9        {
10            public IntPtr hIcon;
11            public int iIcon;
12            public uint dwAttribs;
13            [MarshalAs(UnmanagedType.LPStr, SizeConst=260)]
14            public string pszDisplayName;
15            [MarshalAs(UnmanagedType.LPStr, SizeConst=80)]
16            public string pszTypeName;
17        };
18
19        public enum SHGFI{SmallIcon = 0x00000001,LargeIcon = 0x00000000,ICON=0x000000100,DISPLAYNAME=0x000000200,TYPENAME=0x000000400,SysIconIndex=0x00004000,UseFileAttributes = 0x00000010}
20
21        [DllImport("shell32")]
22        public static extern IntPtr SHGetFileInfo(string pszPath,uint dwAttribs,out SHFileInfo lpfi,int cb,SHGFI flags);
23
24    }
25    
26
27    
28}
29

调用API函数，并生成ico文件

 1private void button1_Click(object sender, System.EventArgs e)
 2        {
 3            //通过下面得到ICON
 4            string filename=this.textBox1.Text.Trim();
 5            string strPath="";
 6            string strNewFile="";
 7            GetAppIcon.GetAppIconApi.SHFileInfo fileiconinfo=new GetAppIcon.GetAppIconApi.SHFileInfo();
 8            GetAppIcon.GetAppIconApi.SHGetFileInfo(filename,0,out fileiconinfo,Marshal.SizeOf(fileiconinfo),GetAppIcon.GetAppIconApi.SHGFI.ICON|GetAppIcon.GetAppIconApi.SHGFI.SmallIcon);
 9            try
10            {
11                Icon thefileicon=Icon.FromHandle(fileiconinfo.hIcon);
12                this.Icon=thefileicon;
13                strPath=Application.StartupPath+"\\";
14                strNewFile="ff"+".ico";
15                strNewFile=strPath+strNewFile;
16                System.Drawing.Bitmap oBp;
17                oBp=this.Icon.ToBitmap();
18                oBp.Save(strNewFile,System.Drawing.Imaging.ImageFormat.Icon);
19                //先将图标转换成bitmap文件再将bitMap文件转换成ico文件
20
21            }
22            catch(Exception ex)
23            {
24                MessageBox.Show("该文件图标无效,请重新选择图标");
25            }
26        
27        }

加入生成的ICO文件不能直接作为窗体的ICO,会报错"参数Picture必须是可用作ICO的图片，我研究过，问题应该是    
 oBp=this.Icon.ToBitmap();
      oBp.Save(strNewFile,System.Drawing.Imaging.ImageFormat.Icon);
在保存时应该根据ico文件的格式进行设置，后来一直没有成功
如果想将其他窗体的图标换成刚才生成的图标，可以如下方法

 1
 2            Image oImage;
 3            System.Drawing.Bitmap bp;
 4            bp=new Bitmap(@"c:\ff.ico");
 5            try
 6            {    
 7                this.Icon=Icon.FromHandle(bp.GetHicon());
 8            }
 9            catch(Exception ex)
10            {
11                MessageBox.Show(ex.Message);
12            }

这是窗体中的ico图标改变