how do i convert this code to VB? i am new in VB.Pls help.

ABC (int xyz)
    If xyz==0
    return (xyz + ABC(xyz-1));

Something like this should work:

Private Function ABC(ByVal xyz As Integer) As Integer
    If xyz = 0 Then
        ABC = 0
        ABC = xyz + ABC(xyz - 1)
    End If
End Function

It's hard to be 100% sure since the code you submitted isn't consistent, and you haven't mentioned what exactly you're trying to do with the code. However it does look like you're trying get the sum of all the digits preceding the input down to 0. If that is the case this code will work. For instance inputting a value of 10 produces an output of 55.