Instrução Function

Define uma sub-rotina que pode ser utilizada como uma expressão para determinar um tipo de retorno.

Sub, Function or Property statements are similar methods, without distinction. They receive parameters by reference allowing them to be modified in return. LibreOffice Basic compiler accepts their respective argument syntax to be used interchangeably.

Sintaxe:

Function Statement diagram


  [Private | Public] Function Name[char] (argument1 [As Type][, argument2[char][,...]]) [As typename]
          statements
      [Exit Function]
          statements
  End Function

Parâmetros:

scope: Function default scope is Public. A Private scope denotes a module internal routine, not intended to be used from other modules.

name: Name of the subroutine to contain the value returned by the function.

arguments: Parameters to be passed to the subroutine.

argument fragment


      {[Optional [ByRef|ByVal]]|ParamArray} argument {{As typename|char}[ = expression]|[()]As Variant}

Parameters

Optional: The argument is not mandatory.

ByRef: The argument is passed by reference. ByRef is the default.

ByVal: The argument is passed by value. Its value can be modified by the called routine.

char: Type declaration character.

typename: Primitive data type name. Library or module defined types can also be specified.

= expression: Specify a default value for the argument, matching its declared type. Optional is necessary for each argument specifying a default value.

ParamArray: Use ParamArray when the number of parameters is undetermined. A typical scenario is that of a Calc user-defined function. Using ParamArray should be limited to the last argument of a routine.

UsingParamArray or = expression require Option Compatible to be placed before the executable program code in a module.

When using Option VBASupport 1, Optional arguments with no default value (= expression) are initialized according to their data type, except if Variant.

typename fragment

primitive data types fragment


      {Boolean|Byte|Currency|Date|Double|Integer|Long|Object|Single|String|Variant}

char fragment

type declaration characters


      { % | & | ! | # | $ | @ }

Examples:


Sub ExampleExit
Dim sReturn As String
Dim sListArray(10) As String
Dim siStep As Single
    For siStep = 0 To 10 ' Preencher matriz com dados de teste
        sListArray(siStep) = chr$(siStep + 65)
        MsgBox sListArray(siStep)
    Next siStep
    sReturn = LinSearch(sListArray(), "B")
    Print sReturn
End Sub
 
Function LinSearch( sList(), sItem As String ) As Integer
Dim iCount As Integer
' Linsearch procura uma TextArray:sList() para TextEntry:
' O valor devolvido é o índice da entrada ou 0 (Null)
    For iCount=1 To Ubound( sList() )
        If sList( iCount ) = sItem Then
            Encontrado Exit For ' sItem
        End If
    Next iCount
    If iCount = Ubound( sList() ) Then iCount = 0
    LinSearch = iCount
End Function