Assigned

function Assigned (var P ):Boolean;

The assigned function checks if a reference is null. Returns True if non-zero, False if zero. Using a Nil reference will result in an exception.

Example

var
 myValue : Integer;
 myValue2 :Integer;
 valueStr : String;

{
 myValue = 10;
 if (Assigned(myValue))
 ShowMessage('myValue is not nil')
 else ShowMessage('myValue is nil');
  
 myValue2 = Nil;
 if (Assigned(myValue2))
 ShowMessage('myValue2 is still not nil')
 else ShowMessage('myValue2 is nil');
  
 if (Assigned(valueStr))
 ShowMessage('valueStr is still not nil')
 else ShowMessage('valueStr is nil');
}

Output:

myValue is not nil
myValue2 is nil
valueStr is nil

See Also

• Boolean Functions