Archive for Byte, Byte to String without delay Delphi [duplicate] - delphi

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Convert Array of ShortInt to String, Delphi
I would like to turn a file into a string, this string should contain the numbers corresponding to the file in bytes.
I did in a way but it was very slow, using an array of FOR and ShortInt ...
Example:
have any file on my computer, my goal would be to transform it into Bytes, Bytes that these should be between -127 .. 128, it would have with something like this:
A[0] = 120
A[1] = -35
A[2] = 40
Ate here OK, but I need it in a concatenated string and a ',' between them, thus:
'120,-35,40'
I did it with a 'FOR', but it was very slow, if you have another alternative.

Answer 1

This question is rather similar to your previous question, but with the added complexity of reading the array from a file.
I'd probably write it like this:
function ConvertFileToCommaDelimitedArray(const FileName: string): string;
var
i, BytesLeft, BytesRead: Integer;
Buffer: array [0..4096-1] of Shortint;
Stream: TFileStream;
sb: TStringBuilder;
begin
sb := TStringBuilder.Create;
try
Stream := TFileStream.Create(FileName, fmOpenRead or fmShareDenyWrite);
try
BytesLeft := Stream.Size;
while BytesLeft>0 do
begin
BytesRead := Min(SizeOf(Buffer), BytesLeft)
Stream.ReadBuffer(Buffer, BytesRead);
dec(BytesLeft, BytesRead);
for i := 0 to BytesRead-1 do
begin
sb.Append(IntToStr(Buffer[i]));
sb.Append(',');
end;
end;
finally
Stream.Free;
end;
if sb.Length>0 then
sb.Length := sb.Length-1;//remove trailing comma
Result := sb.ToString;
finally
sb.Free;
end;
end;

Answer 2

You can load a file into an array of one-byte signed integral types (also known as ShortInt) like this:
type
TShortIntArray = array of TShortInt;
function LoadFileAsShortInt(const name: TFileName): TShortIntArray;
var
f: TFileStream;
begin
f := TFileStream.Create(name, fmOpenRead or fmShareDenyWrite);
try
SetLength(Result, f.Size);
f.ReadBuffer(Result[0], f.Size);
finally
f.Free;
end;
end;
If you want the file's contents as a string, then you should skip the array and load the file directly into a string:
function FileAsString(const name: TFileName): AnsiString;
var
s: TStringStream;
begin
s := TStringStream.Create;
try
s.LoadFromFile(name);
Result := s.DataString;
finally
s.Free;
end;
end;