RFC call thru Excel

Question

Hi,
I am trying to call a RFC (ZTAB_FIELD_DET) by using VBA
as I am new to this feature I dont know much about the possible causes of some errors.
here is the code of RFC which will accept the table name, field name and language. And in turn it will return the Datatype of the field its length and description
**************************RFC Start*******************************:
FUNCTION ZTAB_FIELD_DET.
""Local Interface:
*"  IMPORTING
*"     VALUE(I_TNAME) TYPE  TABNAME
*"     VALUE(I_FNAME) TYPE  FIELDNAME
*"     VALUE(I_LANG) TYPE  LANG
*"  EXPORTING
*"     VALUE(E_DATATYPE) TYPE  DATATYPE_D
*"     VALUE(E_FIELDLENGTH) TYPE  DDLENG
*"     VALUE(E_DESC) TYPE  STRING
*temporary FM created which can retrieve the field details of a table
  DATA : BEGIN OF wa,
    datatype LIKE dd03l-datatype,
    leng LIKE dd03l-leng,
    reptext LIKE dd03m-reptext,
         END OF wa,
    itab LIKE TABLE OF wa.
  SELECT ldatatype lleng m~reptext
   INTO CORRESPONDING FIELDS OF TABLE itab
   FROM ( dd03l AS l JOIN dd03m AS m
               ON lfieldname EQ mfieldname AND
                  ltabname EQ mtabname )
   WHERE l~tabname EQ i_tname AND
         l~fieldname EQ i_fname AND
        m~ddlanguage EQ i_lang.
  LOOP AT itab INTO wa.
    e_datatype = wa-datatype.
    e_fieldlength = wa-leng.
    e_desc = wa-reptext.
  ENDLOOP.
ENDFUNCTION.
*********************RFC End**********************************
and now here is the code that i use in VBA
'*****************VBA start******************************
Set functionCtrl = CreateObject("SAP.Functions")
Set sapConnection = functionCtrl.Connection
sapConnection.client = "xxx"
sapConnection.user = "xxx"
sapConnection.Language = "xxx"
sapConnection.hostname = "xxx"
sapConnection.Password = "xxx"
sapConnection.SystemNumber = "xxx"
sapConnection.Destination = "xxx"
If sapConnection.logon(0, False) <> True Then
MsgBox "No connection to R/3!"
Exit Sub 'End program
Else
MsgBox "Connection to R/3 successful"
' adding the RFC to functionCtrl Object
Set RfcCallTransaction = functionCtrl.Add("ZTAB_FIELD_DET")
RfcCallTransaction.imports("I_TNAME") = "MAKT"
RfcCallTransaction.imports("I_FNAME") = "MAKTG"
RfcCallTransaction.imports("I_LANG") = "EN"
If RfcCallTransaction.Call = True Then
   MsgBox "Datatype" + RfcCallTransaction.imports("E_DATATYPE").Value
   MsgBox "FieldLength" + RfcCallTransaction.imports("E_FIELDLENGTH").Value
   MsgBox "Description" + RfcCallTransaction.imports("E_DESC").Value
   Else
        MsgBox " Call Failed! error: " + GetCustomers.Exception
        functionCtrl.Connection.Logoff
   End If
End sub
'************************VBA End*****************************************
When I run this code, connection to SAP is successful but the
>><i>Set RfcCallTransaction = functionCtrl.Add("ZTAB_FIELD_DET")</i>
shows 'RfcCallTransaction' value as 'Nothing'
and the error message thrown is
"SAP Datatype not supported"
and in the debugger it throws
"Object variable or with block variable not set"
Need your valuable inputs on this
Thanks in advance!
Ranjit.

Answer 1

It was a problem with type of export params
after correction it got solved