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如题

Dim Filter As String
With e.Form.Controls("cmbProduct")
    If .Value IsNot Nothing Then
        Filter = "产品 = '" & .Value & "'"
    End If
End With
With e.Form.Controls("cmbCustomer")
    If .Value IsNot Nothing Then
        If Filter > "" Then
            Filter = Filter & " And "
        End If
        Filter = Filter & "客户 = '" & .Value & "'"
    End If
End With

为什么第二段代码要加上 If Filter f Filter > "" then

Filter = Filter & " And "
End If

而第一段没有呢? 另外大于号和双引号一起用 > ""代表什么意思呢?

主题：帮助文件中疑点