请教Getfileversion问题

[zhaoye2000]

function GetBuildInfo(FName:string):TSimpleVersion;
var
VerInfoSize: DWORD;
VerInfo: Pointer;
VerValueSize: DWORD;
VerValue: PVSFixedFileInfo;
Dummy: DWORD;
V1, V2, V3, V4: Word;
begin
FName为：c:\winnt\explorer.exe，文件版本号为：5.0.3315.2846
VerInfoSize := GetFileVersionInfoSize(PChar(FName), Dummy);
if VerInfoSize>0 then VerInfo:=nil;
GetMem(VerInfo, VerInfoSize);
GetFileVersionInfo(PChar(ParamStr(0)), 0, VerInfoSize, VerInfo);
//上一句执行完后VerInfo值为$DD9B24
VerQueryValue(VerInfo, '\', Pointer(VerValue), VerValueSize);
//上一句执行完后,VerValue值为$11,但下面的WITH语句无法执行
with VerValue^ do//
begin
V1 := dwFileVersionMS shr 16;
V2 := dwFileVersionMS and $FFFF;
V3 := dwFileVersionLS shr 16;
V4 := dwFileVersionLS and $FFFF;
end;
FreeMem(VerInfo, VerInfoSize);
end;
这样，我无法得到文件的版本号，我也不知道问题的所在。

[CloneCenter]

VCL Source comctrls.pas:

function GetComCtlVersion: Integer;
var
FileName: string;
InfoSize, Wnd: DWORD;
VerBuf: Pointer;
FI: PVSFixedFileInfo;
VerSize: DWORD;
begin
if ComCtlVersion = 0 then
begin
// GetFileVersionInfo modifies the filename parameter data while parsing.
// Copy the string const into a local variable to create a writeable copy.
FileName := ComCtlDllName;
InfoSize := GetFileVersionInfoSize(PChar(FileName), Wnd);
if InfoSize <> 0 then
begin
GetMem(VerBuf, InfoSize);
try
if GetFileVersionInfo(PChar(FileName), Wnd, InfoSize, VerBuf) then
if VerQueryValue(VerBuf, '\', Pointer(FI), VerSize) then
ComCtlVersion := FI.dwFileVersionMS;
finally
FreeMem(VerBuf);
end;
end;
end;
Result := ComCtlVersion;
end;