delphi - 能否从 Vista Shell 获取 48x48 或 64x64 图标？

Question

如果 Vista Shell 中存在 48x48 或 64x64 图标，如何使用 SHGetFileInfo 获得在 TImage 中显示图标的句柄？

我想从图像列表中选择一个代表文件夹路径的图标，并在 Timage 中显示 48x48 或 64x64 图标。

// load the large system image for the current path into Image1
SHGetFileInfo( PChar( CurrentPath ), FILE_ATTRIBUTE_NORMAL, SFI,
             SizeOf( TSHFileInfo ), SHGFI_ICON or SHGFI_LARGEICON or SHGFI_SHELLICONSIZE or
             SHGFI_SYSICONINDEX or SHGFI_TYPENAME or SHGFI_DISPLAYNAME );
AImageIndex := SFI.iIcon;
ImageList2.GetBitmap( AImageIndex, Image1.Picture.Bitmap );

比尔

Answer 1

您必须使用SHGetImageList函数，获取具有较大图标的图像列表。

这里有一个 delphi 示例

uses ShellApi, Commctrl, ShlObj;

const
  SHIL_LARGE     = $00;  //The image size is normally 32x32 pixels. However, if the Use large icons option is selected from the Effects section of the Appearance tab in Display Properties, the image is 48x48 pixels.
  SHIL_SMALL     = $01;  //These images are the Shell standard small icon size of 16x16, but the size can be customized by the user.
  SHIL_EXTRALARGE= $02;  //These images are the Shell standard extra-large icon size. This is typically 48x48, but the size can be customized by the user.
  SHIL_SYSSMALL  = $03;  //These images are the size specified by GetSystemMetrics called with SM_CXSMICON and GetSystemMetrics called with SM_CYSMICON.
  SHIL_JUMBO     = $04;  //Windows Vista and later. The image is normally 256x256 pixels.
  IID_IImageList: TGUID= '{46EB5926-582E-4017-9FDF-E8998DAA0950}';

function GetImageListSH(SHIL_FLAG:Cardinal): HIMAGELIST;
type
  _SHGetImageList = function (iImageList: integer; const riid: TGUID; var ppv: Pointer): hResult; stdcall;
var
  Handle        : THandle;
  SHGetImageList: _SHGetImageList;
begin
  Result:= 0;
  Handle:= LoadLibrary('Shell32.dll');
  if Handle<> S_OK then
  try
    SHGetImageList:= GetProcAddress(Handle, PChar(727));
    if Assigned(SHGetImageList) and (Win32Platform = VER_PLATFORM_WIN32_NT) then
      SHGetImageList(SHIL_FLAG, IID_IImageList, Pointer(Result));
  finally
    FreeLibrary(Handle);
  end;
end;


Procedure GetIconFromFile(aFile:String; var aIcon : TIcon;SHIL_FLAG:Cardinal);
var
  aImgList    : HIMAGELIST;
  SFI         : TSHFileInfo;
Begin
    //Get the index of the imagelist
    SHGetFileInfo(PChar(aFile), FILE_ATTRIBUTE_NORMAL, SFI,
                 SizeOf( TSHFileInfo ), SHGFI_ICON or SHGFI_LARGEICON or SHGFI_SHELLICONSIZE or
                 SHGFI_SYSICONINDEX or SHGFI_TYPENAME or SHGFI_DISPLAYNAME );

    if not Assigned(aIcon) then
    aIcon:= TIcon.Create;
    //get the imagelist
    aImgList:= GetImageListSH(SHIL_FLAG);
    //extract the icon handle
    aIcon.Handle:= ImageList_GetIcon(aImgList, Pred(ImageList_GetImageCount(aImgList)), ILD_NORMAL);
End;

你可以这样使用这些功能

var
 hicon :TIcon;
begin
    hicon:= TIcon.Create;
    try
     GetIconFromFile('C:\Tools\reflector\readme.htm',hicon,SHIL_JUMBO);
     Image1.Picture.Icon.Assign(hIcon); //assign to timage
    finally
     hIcon.Free;
    end;
end;