如何避免VBA Userform Combobox输入异常时触发运行时错误？

报错的核心原因是Find方法没有匹配到结果时会返回Nothing，此时直接访问.Offset属性就会触发「Object variable not set」运行时错误，只需先对Find返回结果做非空判断即可解决。

方案1：输入无效时自动重置为空 #

Private Sub ComboBox1_Change()
    Dim findRng As Range
    If ComboBox1.Value = "" Then
        Label3.Caption = ""
    Else
        ' 接收Find方法返回结果，添加LookAt参数实现严格完全匹配
        Set findRng = Worksheets("Currency").Cells.Find(UserForm1.ComboBox1.Value, LookAt:=xlWhole)
        If findRng Is Nothing Then
            ' 未匹配到内容则清空组合框输入
            ComboBox1.Value = ""
        Else
            Label3.Caption = findRng.Offset(0, -1).Value
        End If
    End If
End Sub

Private Sub UserForm_Initialize()
    ComboBox1.List = [Currency!C2:C168].Value
    Label3.Caption = ""
End Sub

方案2：输入无效时弹出错误提示 #

Private Sub ComboBox1_Change()
    Dim findRng As Range
    If ComboBox1.Value = "" Then
        Label3.Caption = ""
    Else
        Set findRng = Worksheets("Currency").Cells.Find(UserForm1.ComboBox1.Value, LookAt:=xlWhole)
        If findRng Is Nothing Then
            ' 弹出无效输入提示
            MsgBox "Invalid Input", vbExclamation
            ' 如需同时清空输入可取消注释下行代码
            ' ComboBox1.Value = ""
        Else
            Label3.Caption = findRng.Offset(0, -1).Value
        End If
    End If
End Sub

Private Sub UserForm_Initialize()
    ComboBox1.List = [Currency!C2:C168].Value
    Label3.Caption = ""
End Sub

内容的提问来源于stack exchange，提问作者Drawleeh