How to append one array to another array of same type in Delphi?

Question

How to append one array to another array of the same type without using iterative statements (for or while loops) in Delphi?

Answer 1

In the last Delphi versions (XE7+) you can just use + operator or Concat routine to append arrays. Link. Official help (doesn't mention +)

Otherwise write your own procedure (use generic arrays if possible). Quick example (checked in XE3):

type 
TArrHelper = class
  class procedure AppendArrays(var A: TArray; const B: TArray);
end;


class procedure TArrHelper.AppendArrays(var A: TArray;
  const B: TArray);
var
  i, L: Integer;
begin
  L := Length(A);
  SetLength(A, L + Length(B));
  for i := 0 to High(B) do
    A[L + i] := B[i];
end;

usage:

var
  A, B: TArray;
begin
  A := TArray.Create('1', '2', '3');
  B := TArray.Create('4', '5');
  TArrHelper.AppendArrays(A, B);