/// <summary>
/// 保存文件信息的结构体
/// </summary>
///
[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Auto)]
struct SHFILEINFO
{public IntPtr hIcon;public int iIcon;public uint dwAttributes;[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 260)]public string szDisplayName;[MarshalAs(UnmanagedType.ByValTStr, SizeConst = 80)]public string szTypeName;
}class NativeMethods
{[DllImport("Shell32.dll", EntryPoint = "SHGetFileInfo", SetLastError = true, CharSet = CharSet.Auto)]public static extern IntPtr SHGetFileInfo(string pszPath, uint dwFileAttributes, ref SHFILEINFO psfi, uint cbFileInfo, uint uFlags);[DllImport("User32.dll", EntryPoint = "DestroyIcon")]public static extern int DestroyIcon(IntPtr hIcon);#region API 参数的常量定义public const uint SHGFI_ICON = 0x100;public const uint SHGFI_LARGEICON = 0x0; //大图标 32×32public const uint SHGFI_SMALLICON = 0x1; //小图标 16×16public const uint SHGFI_USEFILEATTRIBUTES = 0x10;#endregion}
/// <summary>
/// 获取文件类型的关联图标
/// </summary>
/// <param name="fileName">文件类型的扩展名或文件的绝对路径</param>
/// <param name="isLargeIcon">是否返回大图标</param>
/// <returns>获取到的图标</returns>
static Icon GetIcon(string fileName, bool isLargeIcon)
{SHFILEINFO shfi = new SHFILEINFO();IntPtr hI;if (isLargeIcon)hI = NativeMethods.SHGetFileInfo(fileName, 0, ref shfi, (uint)Marshal.SizeOf(shfi), NativeMethods.SHGFI_ICON | NativeMethods.SHGFI_USEFILEATTRIBUTES | NativeMethods.SHGFI_LARGEICON);elsehI = NativeMethods.SHGetFileInfo(fileName, 0, ref shfi, (uint)Marshal.SizeOf(shfi), NativeMethods.SHGFI_ICON | NativeMethods.SHGFI_USEFILEATTRIBUTES | NativeMethods.SHGFI_SMALLICON);Icon icon = Icon.FromHandle(shfi.hIcon).Clone() as Icon;NativeMethods.DestroyIcon(shfi.hIcon); //释放资源return icon;
}private void linkLabel1_LinkClicked(object sender, LinkLabelLinkClickedEventArgs e)
{Help.ShowHelp(this, "http://www.zu14.cn");
}private void btnGetIcon_Click(object sender, EventArgs e)
{using (Graphics g = this.pbSmallIcon.CreateGraphics()){g.Clear(this.pbSmallIcon.BackColor); //清除picturebox的背景色，为了画透明图标g.DrawIcon(GetIcon(this.tbFileExt.Text, false), 1, 1); //绘制小图标}using (Graphics g = this.pbLargeIcon.CreateGraphics()){g.Clear(this.pbLargeIcon.BackColor); //清除picturebox的背景色，为了画透明图标g.DrawIcon(GetIcon(this.tbFileExt.Text, true), 1, 1); //绘制小图标}
}