Correct way to merge multiple TBytes

[FlameFox]

What is the correct way to merge multiple TBytes ?

[lucamar]

Assuming you mean  SysUtils.TBytes, as with any other array: depends on what you want the end result to be. A simple concatenation can be done e.g. with Move():

Code: Pascal  [Select][+][-]

1. function JoinBytes(const a, b: TBytes): TBytes;
2. begin
3.   SetLength(Result, Length(a)+Length(b);
4.   if Length (Result) > 0 then begin
5.     if Length(a) > 0 then Move(a[0], Result[0], Length(a));
6.     if Length(b) > 0 then Move(b[0], Result[Length(a)], Length(b));
7.   end;
8. end;

[FlameFox]

Thanks!

[engkin]

Use Concat:

Code: Pascal  [Select][+][-]

1. var
2.   a,b,c,d,Res: TBytes;
3. ...
4. begin
5. ...
6.   Res := Concat(a,b,c,d);

[wp]

Or, in fpc trunk, you can even use the '+' operator:

Code: Pascal  [Select][+][-]

1. program Project1;
2.  
3. {$mode delphi}
4.  
5. uses
6.   SysUtils;
7.  
8. var
9.   a, b, c: TBytes;
10.   i: byte;
11.  
12. begin
13.   a := [1, 2, 3];
14.   b := [5, 6, 7, 8, 9];
15.   c := a + b;
16.   for i in c do
17.     WriteLn(i);
18.  
19.   ReadLn;
20. end.

[PascalDragon]

Or, in fpc trunk, you can even use the '+' operator:

FPC 3.2.0 is enough.
Though in non-Delphi modes one needs to use $Modeswitch ArrayOperators (the Concat, which was added at the same time, does not require that).

[FlameFox]

Thanks to everybody!