أنظر لهذا التعديل وستعجب له
Function Sum(ByVal First As String, ByVal second As String) As Byte
Dim total As String
total = First + second
Return total
End Function
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
MsgBox(Sum("255", "1"))
End Sub
ستجد أن الخطأ ظهر فى سطر Return total