提取航班号列的值的字符到“号1”和“号2”列中,输入航班列后运行正常,但如重置“航班号”列则会出现:
此主题相关图片如下:417字符串.jpg
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表事件如下:If e.DataCol.Name = "航班号" Then
'Dim fdr As DataRow
Dim dr As DataRow = e.DataRow
Dim s As String = dr("航班号")
If dr("航班号") Is Nothing Then
dr("号1") = Nothing
dr("号2") = Nothing
Else
dr("号1") = s.Chars(0)
dr("号2") = s.Chars(1)
End If
End If
请问原因,谢谢