Mega Code Archive
How to check, if two files are equal
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Title: How to check, if two files are equal
{1.}
function Are2FilesEqual(const File1, File2: TFileName): Boolean;
var
ms1, ms2: TMemoryStream;
begin
Result := False;
ms1 := TMemoryStream.Create;
try
ms1.LoadFromFile(File1);
ms2 := TMemoryStream.Create;
try
ms2.LoadFromFile(File2);
if ms1.Size = ms2.Size then
Result := CompareMem(ms1.Memory, ms2.memory, ms1.Size);
finally
ms2.Free;
end;
finally
ms1.Free;
end
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
if Opendialog1.Execute then
if Opendialog2.Execute then
if Are2FilesEqual(Opendialog1.FileName, Opendialog2.FileName) then
ShowMessage('Files are equal.');
end;
{********************************************}
{2.}
function FilesAreEqual(const File1, File2: TFileName): Boolean;
const
BlockSize = 65536;
var
fs1, fs2: TFileStream;
L1, L2: Integer;
B1, B2: array[1..BlockSize] of Byte;
begin
Result := False;
fs1 := TFileStream.Create(File1, fmOpenRead or fmShareDenyWrite);
try
fs2 := TFileStream.Create(File2, fmOpenRead or fmShareDenyWrite);
try
if fs1.Size = fs2.Size then
begin
while fs1.Position .Size do
begin
L1 := fs1.Read(B1[1], BlockSize);
L2 := fs2.Read(B2[1], BlockSize);
if L1 L2 then
begin
Exit;
end;
if not CompareMem(@B1[1], @B2[1], L1) then Exit;
end;
Result := True;
end;
finally
fs2.Free;
end;
finally
fs1.Free;
end;
end;
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