| Description |
The Begin keyword is fundamental to Delphi - it starts statement blocks.
The Begin-end pair fence in a set of statements. You may place such a block anywhere in your code.
It is particularly sensible in if and for statements, even if only one statement is required. It means that adding an additional statement in the future is easy.
For example :
if a = 7 then do
Inc(b, a);
Is better written :
if a = 7 then do
begin
Inc(b, a);
end;
for maintenance purposes.
|
|
| Related commands |
| End |
|
Keyword that terminates statement blocks |
| For |
|
Starts a loop that executes a finite number of times |
| Function |
|
Defines a subroutine that returns a value |
| Procedure |
|
Defines a subroutine that does not return a value |
| Repeat |
|
Repeat statements until a ternmination condition is met |
| While |
|
Repeat statements whilst a continuation condition is met |
|
|
|
| Example code : Some examples of the begin statement |
// Full Unit code.
// -----------------------------------------------------------
// You must store this code in a unit called Unit1 with a form
// called Form1 that has an OnCreate event called FormCreate.
unit Unit1;
interface
uses
SysUtils,
Forms, Dialogs;
type
TForm1 = class(TForm)
procedure FormCreate(Sender: TObject);
end;
var
Form1: TForm1;
implementation
{$R *.dfm} // Include form definitions
procedure TForm1.FormCreate(Sender: TObject);
var
myChars : array[1..2] of char;
myBytes : array[1..2] of Byte;
i : Integer;
// The begin statement always starts the code part of a subroutine
Begin
// Use a for block to assign to both arrays
for i := 1 to 2 do
Begin
myChars[i] := Chr(i+64);
myBytes[i] := i+64;
end;
// Use a for block to observe the contents
for i := 1 to 2 do
Begin
ShowMessage('myChars['+IntToStr(i)+'] = '+myChars[i]);
ShowMessage('myBytes['+IntToStr(i)+'] = '+IntToStr(myBytes[i]));
end;
end;
end.
|
| Hide full unit code |
myChars[1] = A
myBytes[1] = 65
myChars[2] = B
myChars[2] = 66
|
|