System.VarArrayRedim Function

Resizes a Variant array.

Pascal

procedure VarArrayRedim(A: Variant; HighBound: Integer);

C++

VarArrayRedim(Variant A, int HighBound);

File

System

Description

VarArrayRedim resizes the given Variant array by changing the high bound of the rightmost dimension to the given value. The A parameter can be a Variant or an OleVariant, and it must be possible to assign a value to A (A must be an lvalue).

Existing elements of the array are preserved, and new elements are set to zero or empty. An EVariantArrayCreateError exception is thrown if the Variant given by A is not an array, or if there is not enough memory to resize the array.

Note: A Variant array can't be resized while it is locked.

C++ Examples:

Copy Code

/*
This example demonstrates the use of variant arrays. In this
example a variant array is created, modified, populated and then freed.
*/
void __fastcall TForm1::Button1Click(TObject *Sender)
{
    Variant array;
    int bounds[2] = {0, 9};

    /*
    Create a variant array of 10 elements, starting at 0
    and ending at 9. The array contains elements of type integer
    */
    array = VarArrayCreate(bounds, 1, varInteger);

    // Increase the length of the variant array
    VarArrayRedim(array, 49);

    MessageDlg(String("Variant array has ") + IntToStr(VarArrayDimCount(array)) +
        " dimensions", mtInformation, TMsgDlgButtons() << mbOK, 0);

    // Traverse the array from lower to higher bounds
    for (int i = VarArrayLowBound(array, 1); i <= VarArrayHighBound(array, 1); i++)
    {
        // Put the element I at index I
        VarArrayPut(array, i, &i, 0);
    }

    // Now read the elements of the array
    for (int i = VarArrayLowBound(array, 1); i <= VarArrayHighBound(array, 1); i++)
    {
        // Put the element I at index I
        if (VarArrayGet(array, &i, 0) != i)
            MessageDlg("Error! Invalid element found at current position!",
                mtError, TMsgDlgButtons() << mbOK, 0);
    }

    // Clear the variant array
    VarClear(array);
}

Delphi Examples:

Copy Code

{
This example demonstrates the use of variant arrays. In this
example a variant array is created, modified, populated and then freed.
}
procedure TForm1.Button1Click(Sender: TObject);
var
  Arr: Variant;
  I: Integer;
begin
  { Create a variant array of 10 elements, starting at 0
    and ending at 9. The array contains elements of type integer }
  Arr := VarArrayCreate([0, 9], varInteger);

  { Increase the length of the variant array }
  VarArrayRedim(Arr, 49);

  MessageDlg('Variant array has ' + IntToStr(VarArrayDimCount(Arr)) + ' dimensions',
      mtInformation, [mbOK], 0);

  { Traverse the array from lower to higher bounds }
  for I := VarArrayLowBound(Arr, 1) to VarArrayHighBound(Arr, 1) do
  begin
    { Put the element I at index I}
    VarArrayPut(Arr, I, [I]);
  end;

  { Now read the elements of the array }
  for I := VarArrayLowBound(Arr, 1) to VarArrayHighBound(Arr, 1) do
  begin
    { Put the element I at index I}
    if VarArrayGet(Arr, [I]) <> I then
      MessageDlg('Error! Invalid element found at current position!', mtError, [mbOK], 0);
  end;

  { Clear the variant array }
  VarClear(Arr);
end;