DelphiBasics
Exit
Procedure
Exit abruptly from a function or procedure System unit
 procedure Exit ;
Description
The Exit procedure abruptly terminates the current function or procedure.
 
If exiting a function, then Result contains the last set value.
 
Warning : use with caution - jumping is a concept at odds with structured coding - it makes code maintenance difficult.
Related commands
Break Forces a jump out of a single loop
Continue Forces a jump to the next iteration of a loop
Goto Forces a jump to a label, regardless of nesting
Halt Terminates the program with an optional dialog
RunError Terminates the program with an error dialog
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Example code : Exit a proc when a user cancels data entry
// 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
  // The System unit does not need to be defined
  Forms, Dialogs;
 
type
  TForm1 = class(TForm)
    procedure FormCreate(Sender: TObject);
    function AskForName: string;
  end;
 
var
  
Form1: TForm1;
 
implementation
{$R *.dfm} // Include form definitions
 
procedure TForm1.FormCreate(Sender: TObject);

begin
  // Ask the user for their name
  ShowMessage('Name = '+AskForName);
end;

// Ask the user for first and second names
function TForm1.AskForName: string;
var
  firstName, secondName : string;
begin
  Result := 'Lazy person';
  repeat
    if not InputQuery('Test program', 'First name :', firstName)
    then Exit;
    if not InputQuery('Test program', 'Second name :', secondName)
    then Exit;
  until (firstName <> '') or (secondName <> '');

  Result := firstName + ' ' + secondName;
end;
 
end.
Hide full unit code
   If the user cancels from the first or second name dialogs, the ShowMessage dialog gives:
  
   Name = Lazy person
 
 
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