Compare Versions as strings in InnoScript. fixed html tags from source article

InnoScript_CompareVersionStrings.iss

// ----------------Compare versions - start ------------------
// source: http://www.arvydas.co.uk/2015/04/compare-version-strings-with-innosetup/
// Procedure to split a string into an array of integers
procedure Explode(var Dest: TArrayOfInteger; Text: String; Separator: String);
var
  i, p: Integer;
begin
  i := 0;
  repeat
    SetArrayLength(Dest, i+1);
    p := Pos(Separator,Text);
    if p > 0 then begin
      Dest[i] := StrToInt(Copy(Text, 1, p-1));
      Text := Copy(Text, p + Length(Separator), Length(Text));
      i := i + 1;
    end else begin
      Dest[i] := StrToInt(Text);
      Text := '';
    end;
  until Length(Text)=0;
end;

// Function compares version strings numerically:
//     * when v1 = v2, result = 0
//     * when v1 < v2, result = -1
//     * when v1 > v2, result = 1
//
// Supports version numbers with trailing zeroes, for example 1.02.05.
// Supports comparison of two version number of different lengths, for example
//     CompareVersions('1.2', '2.0.3')
// When any of the parameters is '' (empty string) it considers version number as 0
function CompareVersions(v1: String; v2: String): Integer;
var
  v1parts: TArrayOfInteger;
  v2parts: TArrayOfInteger;
  i: Integer;
begin
  if v1 = '' then
  begin
    v1 := '0';
  end;

  if v2 = '' then
  begin
    v2 := '0';
  end;

  Explode(v1parts, v1, '.');
  Explode(v2parts, v2, '.');

  if (GetArrayLength(v1parts) > GetArrayLength(v2parts)) then
  begin
    SetArrayLength(v2parts, GetArrayLength(v1parts))
  end else if (GetArrayLength(v2parts) > GetArrayLength(v1parts)) then
  begin
    SetArrayLength(v1parts, GetArrayLength(v2parts))
  end;

  for i := 0 to GetArrayLength(v1parts) - 1 do
  begin
    if v1parts[i] > v2parts[i] then
    begin
      { v1 is greater }
      Result := 1;
      exit;
    end else if v1parts[i] < v2parts[i] then
    begin
      { v2 is greater }
      Result := -1;
      exit;
    end;
  end;

  { Are Equal }
  Result := 0;
end;
// ----------------Compare versions - end ------------------