IfEmpty

The IfEmpty function checks the variant aValue1, and if it is a empty variant variable (it has a vartype equal to 0), then it will return the replacement value of aValue2.

If aValue1 is not empty, then it will return its own value aValue1.

A variable can be forced to empty.

Please also review IfNull, and also the String Function IfBlank.

Declaration: Function IfEmpty( const aValue1, aValue2 : Variant) : Variant;

Several examples are illustrated in the following.

procedure ScriptEvent (var Value : variant);
var
  Emp1, Emp2, Emp3 : variant;
begin
  LogInfo('');
  LogInfo('Emp1 = '+IntToStr(VarType(Emp1)));                    //EMPTY variant variable returns the vartype of 0
  Emp2 := 'Winnie The Pooh';
 
  LogInfo('');
  LogInfo('1st IfEmpty pass . . .');
  Emp3 := IfEmpty(Emp1, 'Param1 is empty');                        //Emp1 is EMPTY
  LogInfo('Emp3 = '+Emp3);                                         //Emp3 is 'Param1 is empty'
 
  LogInfo('');
  LogInfo('2nd IfEmpty pass . . . ');
  Emp3 := IfEmpty(Emp1, Emp2 + ' + Piglet!');                      //Emp1 is EMPTY
  LogInfo('Emp2 = '+Emp2);                                         //Emp2 is 'Winnie The Pooh'
  LogInfo('Emp3 = '+Emp3);                                         //Emp3 is 'Winnie The Pooh + Piglet!'
 
  LogInfo('');
  LogInfo('3rd IfEmpty pass . . . ');
  Emp3 := IfEmpty('', 'This is the replacement value.');          //Param1 is empty
  LogInfo('Emp3 = '+Emp3);                                         //Emp3 is 'This is the replacement value.'
 
  LogInfo('');
  LogInfo('4th IfEmpty pass . . . ');
  Emp3 := IfEmpty('  ', 'Param1 is BLANK');                        //aVarVar is NULL
  LogInfo('Emp3 = '+Emp3);                                         //Emp3 is '   ' (a blank)
 
end;