字符串动态组成的问题！大家帮帮忙！

Question

If Trim(Aclass.Text) <> "" Then
        smallclass1 = Trim(Aclass.Text)
        End If
        If Trim(AnClass.Text) <> "" Then
        smallclass2 = Trim(AnClass.Text)
        End If
        If Trim(Aclass1.Text) <> "" Then
        smallclass3 = Trim(Aclass1.Text)
        End If
        If Trim(Anclass1.Text) <> "" Then
        smallclass4 = Trim(Anclass1.Text)
        End If
        smallclass = smallclass1 & " , " & smallclass2 & ", " & smallclass3 & ", " & smallclass4
如果我现在4个都选那么smallclass 的值刚好是我想要的
但是如果有的是空那么就多了我不想要的,
我不知道这个应该怎么处理，大家帮忙告诉

Answer 1

Private Sub Form_Load()
    Dim SmallClass As String
    SmallClass = ""
    If Trim(Aclass.Text) <> "" Then
        SmallClass = Trim(Aclass.Text)
    End If
    If Trim(AnClass.Text) <> "" Then
        If Trim(SmallClass) = "" Then
            SmallClass = Trim(AnClass.Text)
        Else
            SmallClass = SmallClass & "," & Trim(AnClass.Text)
        End If
    End If
    If Trim(Aclass1.Text) <> "" Then
        If Trim(SmallClass) = "" Then
            SmallClass = Trim(Aclass1.Text)
        Else
            SmallClass = SmallClass & "," & Trim(Aclass1.Text)
        End If
    End If
    If Trim(Anclass1.Text) <> "" Then
        If Trim(SmallClass) = "" Then
            SmallClass = Trim(Anclass1.Text)
        Else
            SmallClass = SmallClass & "," & Trim(Anclass1.Text)
        End If
    End If
    MsgBox SmallClass
End Sub

Answer 2

smallclass = ""
    If Trim(Aclass.Text) <> "" Then
        smallclass = smallclass & Trim(Aclass.Text) & ","
    End If
    If Trim(AnClass.Text) <> "" Then
        smallclass = smallclass & Trim(AnClass.Text) & ","
    End If
    If Trim(Aclass1.Text) <> "" Then
        smallclass = smallclass & Trim(Aclass1.Text) & ","
    End If
    If Trim(Anclass1.Text) <> "" Then
        smallclass = smallclass & Trim(Anclass1.Text) & ","
    End If
    If Len(smallclass) > 1 Then
        '截掉最后的逗号
        smallclass = Left(smallclass, Len(smallclass) - 1)
    End If

Answer 3

If Trim(Aclass.Text) <> "" Then
        smallclass1 = Trim(Aclass.Text)
smallclass=smallclass & smallclass1 & ","
        End If
        If Trim(AnClass.Text) <> "" Then
        smallclass2 = Trim(AnClass.Text)
        smallclass=smallclass & smallclass2 & ","
        End If
        If Trim(Aclass1.Text) <> "" Then
        smallclass3 = Trim(Aclass1.Text)
        smallclass=smallclass & smallclass3 & ","
        End If
        If Trim(Anclass1.Text) <> "" Then
        smallclass4 = Trim(Anclass1.Text)
        smallclass=smallclass & smallclass4 & ","
        End If
        if smallclass<>"" then
        smallclass = left(smallclass,len(smallclass)-1)
        end if

Answer 4

dim smallclass as string
smallclass=""
If Trim(Aclass.Text) <> "" Then
        smallclass = smallclass & Trim(Aclass.Text)
        End If
        If Trim(AnClass.Text) <> "" Then
        smallclass = smallclass & Trim(AnClass.Text)
        End If
        If Trim(Aclass1.Text) <> "" Then
        smallclass = smallclass & Trim(Aclass1.Text)
        End If
        If Trim(Anclass1.Text) <> "" Then
        smallclass = smallclass & Trim(Anclass1.Text)
        End If