获取图标128 * 128文件类型C＃

我需要获取文件类型doc或txt的图标

它的大小应该是128 * 128，并保存为高质量的png或ico文件。

我用了

Icon ico = Icon.ExtractAssociatedIcon(@"d:\\1.txt"); pictureBox1.Image = ico.ToBitmap(); 

并保存pictureBox1中的图像，但该大小为32 * 32。

我真的想要128 * 128的尺寸。

我怎样才能做到这一点？

Answer 1

Shell API SHGetImageList中没有可用的图标大小128×128。 尺寸范围从Win95时代的16×16和32×32到XP的48×48，最后是Vista增加了256×256尺寸。

要从任何可用的图标大小获取png文件，我在博客中如何从Raymond Chen 获取文件的高分辨率图标 。 我将他的代码移植到c＃，我从这个答案中借了一些东西。

要关注Raymond的文章，您需要的主要两个function是：

  int GetIconIndex(string pszFile) { SHFILEINFO sfi = new SHFILEINFO(); Shell32.SHGetFileInfo(pszFile , 0 , ref sfi , (uint)System.Runtime.InteropServices.Marshal.SizeOf(sfi) , (uint) (SHGFI.SysIconIndex | SHGFI.LargeIcon | SHGFI.UseFileAttributes)); return sfi.iIcon; } // 256*256 IntPtr GetJumboIcon(int iImage) { IImageList spiml = null; Guid guil = new Guid(IID_IImageList2);//or IID_IImageList Shell32.SHGetImageList(Shell32.SHIL_JUMBO, ref guil, ref spiml); IntPtr hIcon = IntPtr.Zero; spiml.GetIcon(iImage, Shell32.ILD_TRANSPARENT | Shell32.ILD_IMAGE, ref hIcon); // return hIcon; } 

方法GetIconIndex调用本机SHGetFileIfo以获取您在name参数中提供的文件（或扩展名）的图标索引。

为了获得实际图标，方法GetJumboIcon使用size属性调用本机SHGetImageList 。

为了让它全部工作，你可以像这样组合调用：

 IntPtr hIcon = GetJumboIcon(GetIconIndex("*.txt")); // from native to managed using (Icon ico = (Icon)System.Drawing.Icon.FromHandle(hIcon).Clone()) { // save to file (or show in a picture box) ico.ToBitmap().Save("txticon.png", ImageFormat.Png); } Shell32.DestroyIcon(hIcon); // don't forget to cleanup 

要获得48×48图标，您可以使用以下方法扩展代码：

  // 48X48 IntPtr GetXLIcon(int iImage) { IImageList spiml = null; Guid guil = new Guid(IID_IImageList);//or IID_IImageList Shell32.SHGetImageList(Shell32.SHIL_EXTRALARGE, ref guil, ref spiml); IntPtr hIcon = IntPtr.Zero; spiml.GetIcon(iImage, Shell32.ILD_TRANSPARENT | Shell32.ILD_IMAGE, ref hIcon); // return hIcon; } 

由于与非托管代码的交互，您需要在启用/ unsafe选项的情况下编译项目。 您可以通过更改项目属性从visual studio中进行设置，转到Build选项卡并勾选Allow unsafe code选项。 看到这个问题为什么需要这个， 这是官方的MSDN文档

原生包装

要调用本机win32 api，函数和结构将包装在您需要包含在项目中的静态类中。 大多数包装和结构都可以在Pinvoke.net找到

 const string IID_IImageList = "46EB5926-582E-4017-9FDF-E8998DAA0950"; const string IID_IImageList2 = "192B9D83-50FC-457B-90A0-2B82A8B5DAE1"; public static class Shell32 { public const int SHIL_LARGE =0x0; public const int SHIL_SMALL =0x1; public const int SHIL_EXTRALARGE =0x2; public const int SHIL_SYSSMALL =0x3; public const int SHIL_JUMBO = 0x4; public const int SHIL_LAST = 0x4; public const int ILD_TRANSPARENT = 0x00000001; public const int ILD_IMAGE = 0x00000020; [DllImport("shell32.dll", EntryPoint = "#727")] public extern static int SHGetImageList(int iImageList, ref Guid riid, ref IImageList ppv); [DllImport("user32.dll", EntryPoint = "DestroyIcon", SetLastError = true)] public static unsafe extern int DestroyIcon(IntPtr hIcon); [DllImport("shell32.dll")] public static extern uint SHGetIDListFromObject([MarshalAs(UnmanagedType.IUnknown)] object iUnknown, out IntPtr ppidl); [DllImport("Shell32.dll")] public static extern IntPtr SHGetFileInfo( string pszPath, uint dwFileAttributes, ref SHFILEINFO psfi, uint cbFileInfo, uint uFlags ); } 

原生结构

 [Flags] enum SHGFI : uint { /// 
get icon
 Icon = 0x000000100, /// 
get display name
 DisplayName = 0x000000200, /// 
get type name
 TypeName = 0x000000400, /// 
get attributes
 Attributes = 0x000000800, /// 
get icon location
 IconLocation = 0x000001000, /// 
return exe type
 ExeType = 0x000002000, /// 
get system icon index
 SysIconIndex = 0x000004000, /// 
put a link overlay on icon
 LinkOverlay = 0x000008000, /// 
show icon in selected state
 Selected = 0x000010000, /// 
get only specified attributes
 Attr_Specified = 0x000020000, /// 
get large icon
 LargeIcon = 0x000000000, /// 
get small icon
 SmallIcon = 0x000000001, /// 
get open icon
 OpenIcon = 0x000000002, /// 
get shell size icon
 ShellIconSize = 0x000000004, /// 
pszPath is a pidl
 PIDL = 0x000000008, /// 
use passed dwFileAttribute
 UseFileAttributes = 0x000000010, /// 
apply the appropriate overlays
 AddOverlays = 0x000000020, /// 
Get the index of the overlay in the upper 8 bits of the iIcon
 OverlayIndex = 0x000000040, } [StructLayout(LayoutKind.Sequential)] public struct SHFILEINFO { public const int NAMESIZE = 80; 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; }; [StructLayout(LayoutKind.Sequential)] public struct RECT { public int left, top, right, bottom; } [StructLayout(LayoutKind.Sequential)] public struct POINT { int x; int y; } [StructLayout(LayoutKind.Sequential)] public struct IMAGELISTDRAWPARAMS { public int cbSize; public IntPtr himl; public int i; public IntPtr hdcDst; public int x; public int y; public int cx; public int cy; public int xBitmap; // x offest from the upperleft of bitmap public int yBitmap; // y offset from the upperleft of bitmap public int rgbBk; public int rgbFg; public int fStyle; public int dwRop; public int fState; public int Frame; public int crEffect; } [StructLayout(LayoutKind.Sequential)] public struct IMAGEINFO { public IntPtr hbmImage; public IntPtr hbmMask; public int Unused1; public int Unused2; public RECT rcImage; } [ComImportAttribute()] [GuidAttribute("46EB5926-582E-4017-9FDF-E8998DAA0950")] [InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIUnknown)] public interface IImageList { [PreserveSig] int Add( IntPtr hbmImage, IntPtr hbmMask, ref int pi); [PreserveSig] int ReplaceIcon( int i, IntPtr hicon, ref int pi); [PreserveSig] int SetOverlayImage( int iImage, int iOverlay); [PreserveSig] int Replace( int i, IntPtr hbmImage, IntPtr hbmMask); [PreserveSig] int AddMasked( IntPtr hbmImage, int crMask, ref int pi); [PreserveSig] int Draw( ref IMAGELISTDRAWPARAMS pimldp); [PreserveSig] int Remove( int i); [PreserveSig] int GetIcon( int i, int flags, ref IntPtr picon); [PreserveSig] int GetImageInfo( int i, ref IMAGEINFO pImageInfo); [PreserveSig] int Copy( int iDst, IImageList punkSrc, int iSrc, int uFlags); [PreserveSig] int Merge( int i1, IImageList punk2, int i2, int dx, int dy, ref Guid riid, ref IntPtr ppv); [PreserveSig] int Clone( ref Guid riid, ref IntPtr ppv); [PreserveSig] int GetImageRect( int i, ref RECT prc); [PreserveSig] int GetIconSize( ref int cx, ref int cy); [PreserveSig] int SetIconSize( int cx, int cy); [PreserveSig] int GetImageCount( ref int pi); [PreserveSig] int SetImageCount( int uNewCount); [PreserveSig] int SetBkColor( int clrBk, ref int pclr); [PreserveSig] int GetBkColor( ref int pclr); [PreserveSig] int BeginDrag( int iTrack, int dxHotspot, int dyHotspot); [PreserveSig] int EndDrag(); [PreserveSig] int DragEnter( IntPtr hwndLock, int x, int y); [PreserveSig] int DragLeave( IntPtr hwndLock); [PreserveSig] int DragMove( int x, int y); [PreserveSig] int SetDragCursorImage( ref IImageList punk, int iDrag, int dxHotspot, int dyHotspot); [PreserveSig] int DragShowNolock( int fShow); [PreserveSig] int GetDragImage( ref POINT ppt, ref POINT pptHotspot, ref Guid riid, ref IntPtr ppv); [PreserveSig] int GetItemFlags( int i, ref int dwFlags); [PreserveSig] int GetOverlayImage( int iOverlay, ref int piIndex); };