Functions Delphi

function Slice ( SourceArray : array; Count : Integer ) : array;


Description
The Slice function creates a sub-array from the first Count elements of an array, SourceArray.

It can ONLY be used as an argument for an 'Open array' parameter of a procedure or function.

An 'Open array' parameter is one that has an unknown number of array elements at compile time.

This allows for a routine to work with variable sized arrays.

Related commands
Array A data type holding indexable collections of data
Copy Create a copy of part of a string or an array

Example code : Passing an array slice to a procedure
var
i : Integer;
Source : array[0..4] of Integer;
begin
// Create the source array with 0..4 values for elements 0..4
for i := 0 to 4 do
Source[i] := i;
// Use the Slice command to pass just the first 3 elements of Source as
// an open array to the ShowSlice procedure below.
ShowSlice(Slice(Source, 3));
end;
// Show an array of unknown size - it is passed as an 'Open' array
procedure TForm1.ShowSlice(SubArray : array of Integer);
var
i : Integer;
begin
// Show every element of this array
for i := 0 to Length(SubArray)-1 do
ShowMessage('SubArray['+IntToStr(i)+'] : '+ IntToStr(SubArray[i]));
end;

Show full unit code
SubArray[0] : 0
SubArray[1] : 1
SubArray[2] : 2