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An array variable can be used to store
many data items of the same kind under the same name. Each item is
distinguished from the other using an index.
Arrays must be declared under the var and a range must be set, for example:
var
arrNames : array[1..20] of String;
arrAges : array[1.1000] of Integer;
The array arrNames can contain up to 20 names
(String data type).
The array arrAges can contain up to 1000 integer values.
Dynamic arrays are used in instances where there is no clear indication of how
many items will be used initially.
Data is usually entered into an array
using a loop, for example:
var
Form1: TForm1;
arrNum : array[1..10] of Integer;
implementation
{$R *.DFM}
procedure TForm1.btnEnterNumClick(Sender: TObject);
var
iCount : Integer;
begin
FOR iCount := 1 to 10 do
begin
arrNum[iCount] := iCount * 2;
end;
end;
procedure TForm1.btnDisplayNumClick(Sender: TObject);
var
iCountB : Integer;
begin
FOR iCountB := 1 to 10 do
begin
redOutput.Lines.Add(IntToStr(arrNum[iCountB]));
end;
end;
end.
Take note:
? The array is declared globally so it can be used in more than one procedure.
? The counter used for the FOR loop is also used as index for the array.
? Another loop is used to display the values found in the array.
Data can also be entered into a globally
declared array using an edit box and button (data is then displayed in a ListBox),
for example:
var
Form1: TForm1;
arrNames : array[1..10] of String;
iCount : integer; {Counts entered items}
implementation
{$R *.DFM}
procedure TForm1.btnEnterNameClick(Sender: TObject);
begin
iCount := iCount + 1; {Increases counter}
arrNames[iCount] := edit1.text;
end;
procedure TForm1.FormCreate(Sender: TObject);
begin
iCount := 0; {Initial value of counter}
end;
procedure TForm1.btnDisplayNamesClick(Sender: TObject);
var
iForCounter : integer; {FOR loop counter}
begin
FOR iForCounter := 1 to iCount do
begin
lstNames.Items.Add(arrNames[iForCounter]);
end;
end;
end.
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