Syntax

Declares a function that belongs to a TYPE. Inside it, SELF is the record the method was called on.

METHOD <method>([<parameter>, …])
  SELF.<field>
  EXITMETHOD [<value>]
  RETURN [<value>]
ENDMETHOD
<record>.<method>([<argument>, …])

Also written : ENDMETHOD, EXITMETHOD, SELF

Parts

<method>The method name. Case does not matter. New and Delete are special: see NEW and DELETE.
<parameter>A parameter, written as for a FUNCTION: typed, with a default value, OPTIONAL, REF or variadic.
<field>A field of the record, or another method: SELF.Reset().
<value>The value given back by the method. Optional.
<record>Any record: a variable, an array cell (counters(2)), the current list element (counters()).
<argument>A value passed to the matching parameter.

Good to know

  • A method is declared inside its TYPE, among the fields. The parentheses are required, even empty: METHOD Reset().
  • Writing SELF.value changes the record the method was called on, also when it is an array cell or a list element.
  • EXITMETHOD <value> and RETURN <value> leave the method with a value. ENDMETHOD takes no value, unlike ENDFUNCTION.
  • A method has no return type: METHOD Half() AS integer is refused ("Invalid field in BASIC type"). Convert the value yourself before returning it.
  • Refused at compile time: a METHOD outside a TYPE ("METHOD requires a containing TYPE"), a METHOD inside a METHOD, two methods with the same name in one TYPE, a value after ENDMETHOD, and END METHOD in two words.
  • Do not name a method Length, Find, Sort, Insert or Remove. These names belong to the array members, and the call stops the program.
  • A copy of a record has the same methods. In a program with DO … LOOP, a program variable used by a method must be declared GLOBAL, as for any FUNCTION.

Example

TYPE Counter  value AS integer  METHOD Add(amount AS integer)    SELF.value = SELF.value + amount    EXITMETHOD SELF.value  ENDMETHOD  METHOD Reset()    SELF.value = 0  ENDMETHODENDTYPEc AS CounterConsole(Str(c.Add(5)))   ' 5Console(Str(c.Add(3)))   ' 8c.Reset()Console(Str(c.value))    ' 0
In the manual : Records and methods

See also