delphi write data with updateresources - delphi

Question

I try to write a string to an external exe file, but when i read the string via the other project i get an other string.
Example:
When i write "test123" then i read "test123Click".
When i write "test" then i read "test.".
When i write "name" then i read "name.".
I use this script to write:
procedure WriteSettings(ServerFile: string; Settings: string);
var
ResourceHandle: THandle;
pwServerFile: PWideChar;
begin
GetMem(pwServerFile, (Length(ServerFile) + 1) * 2);
try
StringToWideChar(ServerFile, pwServerFile, Length(ServerFile) * 2);
ResourceHandle := BeginUpdateResourceW(pwServerFile, False);
UpdateResourceW(ResourceHandle, MakeIntResourceW(10), 'SETTINGS', 0, #Settings[1], ByteLength(settings));
EndUpdateResourceW(ResourceHandle, False);
finally
FreeMem(pwServerFile);
end;
end;
This is the script to read:
function LoadSettings: string;
var
ResourceLocation: HRSRC;
ResourceSize: dword;
ResourceHandle: THandle;
ResourcePointer: pointer;
begin
ResourceLocation := FindResource(hInstance, 'SETTINGS', RT_RCDATA);
ResourceSize := SizeofResource(hInstance, ResourceLocation);
ResourceHandle := LoadResource(hInstance, ResourceLocation);
ResourcePointer := LockResource(ResourceHandle);
if ResourcePointer <> nil then
begin
SetLength(Result, ResourceSize - 1);
CopyMemory(#Result[1], ResourcePointer, ResourceSize);
FreeResource(ResourceHandle);
end;
end;
What i am doing wrong?
I use everywhere a normal string, so not ansi and utf8.

Answer 1

You need to write a null terminator. Every time you call UpdateResourceW pass (Length(str)+1)*SizeOf(str[1]) for the byte count parameter.
Also, #Settings[1] will fail for the empty string. I'd use PWideChar() instead. Like so:
UpdateResourceW(ResourceHandle, MakeIntResourceW(10), 'SETTINGS', 0,
PWideChar(Settings), (Length(Settings)+1)*SizeOf(Settings[1]));
Although all the explicit W suffixing is rather needless. You can write:
UpdateResource(ResourceHandle, MakeIntResource(10), 'SETTINGS', 0,
PChar(Settings), (Length(Settings)+1)*SizeOf(Settings[1]));
And the dynamic memory allocation is needless. You can write:
procedure WriteSettings(ServerFile: string; Settings: string);
var
ResourceHandle: THandle;
begin
ResourceHandle := BeginUpdateResource(PChar(ServerFile), False);
UpdateResource(ResourceHandle, MakeIntResource(10), 'SETTINGS', 0,
PChar(Settings), (Length(Settings)+1)*SizeOf(Settings[1]));
EndUpdateResource(ResourceHandle, False);
end;
And you really should include some error checking:
procedure WriteSettings(ServerFile: string; Settings: string);
var
ResourceHandle: THandle;
begin
ResourceHandle := BeginUpdateResource(PChar(ServerFile), False);
Win32Check(ResourceHandle<>0);
Win32Check(UpdateResource(ResourceHandle, MakeIntResource(10), 'SETTINGS', 0,
PChar(Settings), (Length(Settings)+1)*SizeOf(Settings[1])));
Win32Check(EndUpdateResource(ResourceHandle, False));
end;