为什么我加入下列代码后，材料单价就不自动显示了

If e.col.name = "全木盘资_金额" Then
    Dim v As Double
    Double.TryParse(e.text,v)
    If v > 0 Then
        e.Style = "a"
    End If
End If

对自动显示全木盘不同材料的单价，就不能改变了，不知是什么原因？

Dim dr1 As DataRow = e.DataRow
Select Case e.DataCol.Name
    Case "全木盘_材料","规格","全木盘_厚度", "地点"
        Dim dr2 As DataRow
        Dim fls As String
        fls = "名称 = \'" & dr1("全木盘_材料") & "\' And 规格 = \'" & dr1("规格") & "\' And 厚度 = " & dr1("全木盘_厚度") & " And 送货地点  = \'" & dr1("地点") & "\'"
        dr2 = DataTables("参数").Find(fls)
        If dr2 IsNot Nothing Then
        dr1("全木盘_单价") = dr2("单价")
        End If
End Select
请师傅帮忙分析，解决