Title: Check if a file should be overwritten using version control etc.
Question: How can I check if a file should be overwritten or not during a copyfile operation?
Answer:
Below is an example on how you can control if a file should be overwritten or not. Just use:
if VersionCopyFileCheck(file1,file2) then CopyFile(file1,file2,FALSE);
uses SysUtils, Classes, Windows;
//
function GetFileVersion(filename : string; var VerBlk : VS_FIXEDFILEINFO) : boolean;
var InfoSize,puLen : DWord;
Pt,InfoPtr : Pointer;
begin
InfoSize := GetFileVersionInfoSize(PChar(filename),puLen);
fillchar(VerBlk,sizeof(VS_FIXEDFILEINFO),0);
if InfoSize 0 then begin
GetMem(Pt,InfoSize);
GetFileVersionInfo(PChar(filename),0,InfoSize,Pt);
VerQueryValue(Pt,'\',InfoPtr,puLen);
move(InfoPtr^,VerBlk,sizeof(VS_FIXEDFILEINFO));
FreeMem(Pt);
result := true;
end else result := false;
end;
//
function VersionCopyFileCheck(Source,Dest : string) : boolean;
var SourceVer,DestVer : VS_FIXEDFILEINFO;
SourceDate,DestDate : TDateTime;
SourceSize,DestSize : integer;
begin
if FileExists(Dest) then begin
if FileExists(Source) then begin
if (GetFileVersion(Source,SourceVer) and GetFileVersion(Dest,DestVer)) then begin
// Check the version differencies
if (SourceVer.dwProductVersionMS if (SourceVer.dwProductVersionMS = SourceVer.dwProductVersionMS) then begin
result := (SourceVer.dwProductVersionLS DestVer.dwProductVersionLS);
end else result := false;
end else result := true;
end else begin
// There was no version information in the verblock, check the fileage
result := (FileAge(Source,SourceVer) FileAge(Dest,DestVer));
end;
end else result := false; // No copy, Source doesnt exist
end else result := true; // Ok, there is no file that can be overwritten
end;