系统图像列表

uses shellapi; 第一步 取得系统的图标列表的句柄，将之赋予一个图像列表控件。
procedure GetSystemImageList(imagelist:TImageList);
var
SysIL: THandle;
SFI: TSHFileInfo;
begin
// 取小图标，如果将SHGFI_SMALLICON替换成
//SHGFI_LARGEICON则表示取大图标
SysIL := SHGetFileInfo('', 0, SFI, SizeOf(SFI),
SHGFI_SYSICONINDEX or SHGFI_SMALLICON);
if SysIL <> 0 then begin
//将imagelist的图像列表句柄指向系统图像句柄
imagelist.Handle := SysIL;
//防止组件释放时释放图像句柄，很重要
imagelist.ShareImages := TRUE;
end;
end;
第二步 取得要处理文件的图标索引
//取一个文件的图标索引
function GetIconIndex(const AFile: string; Attrs: DWORD): integer;
//Attrs可以为表示文件或路径FILE_ATTRIBUTE_NORMAL or FILE_ATTRIBUTE_DIRECTORY
var
SFI: TSHFileInfo;
begin
SHGetFileInfo(PChar(AFile), Attrs, SFI, SizeOf(TSHFileInfo),
SHGFI_SYSICONINDEX or SHGFI_USEFILEATTRIBUTES);
Result := SFI.iIcon;
end;
//获取一个文件的imageindex;
function GetIconIndex(const APath: string; Attrs: DWORD): integer;
var
SFI: TSHFileInfo;
begin
if FileExists(APath) or DirectoryExists(APath) then
// If the file or directory exists, just let Windows figure out it's attrs.
SHGetFileInfo(PChar(APath), 0, SFI, SizeOf(TSHFileInfo),
SHGFI_SYSICONINDEX)
else
// File doesn't exist, so Windows doesn't know what to do with it. We have
// to tell it by passing the attributes we want, and specifying the
// SHGFI_USEFILEATTRIBUTES flag so that the function knows to use them.
SHGetFileInfo(PChar(APath), Attrs, SFI, SizeOf(TSHFileInfo),
SHGFI_SYSICONINDEX or SHGFI_USEFILEATTRIBUTES);
Result := SFI.iIcon;
end;
实例调用：
//如在TreeView中得到c:的图标，因为是路径所以要加上路径的标志
aNode.ImageIndex := GetIconIndex('c:,
FILE_ATTRIBUTE_NORMAL or FILE_ATTRIBUTE_DIRECTORY);
//如在TreeView中得到c:.html的图标
aNode.ImageIndex := GetIconIndex('c:.html',FILE_ATTRIBUTE_NORMAL);