Local array only taking first four entries of static array

[Harrison]

Alright, in my program, I've got multiple static arrays ranging in size from 1 to 61. They are all array of string. Let's call them "Array1", "Array2", "Array3".

In a procedure, I have a local array that dependent on user input, is meant to become one of the arrays. So I have code like this:

Code: [Select]

if userinput = 1 then
  begin
    Areas := Array1;
  end
else if userinput = 2 then
  begin
    Areas := Array2;
  end
else if userinput = 3 then
  begin
    Areas := Array3;
  end;

for I := 0 to SizeOf(Areas) do
  begin
    AreaCombo.AddItem(Areas[I],AreaCombo);
  end;

However, only four entries get added to AreaCombo, and sending SizeOf to my debug box shows that it's only a size of 4.

Why is it limiting itself to only four?

[Leledumbo]

If Areas is a dynamic array, SizeOf() will return size of pointer. This is due to dynamic arrays treated internally as pointers. Use Length() instead.

[Harrison]

Ah, awesome, thanks.

Might I ask what exactly the use of pointers like that are?

[Leledumbo]

Might I ask what exactly the use of pointers like that are?

Pointers are (mainly) used for dynamic memory allocation. In modern Pascal, this includes dynamic array, ansi- and wide-strings and classes (add more if I miss the others).