简单判断一下

 

Dim drs As List(of DataRow) = DataTables("时间").Select("选择 = True")
For Each dr As DataRow In drs
    Dim dr1 As DataRow = DataTables("月").AddNew
    For Each dc As DataCol In DataTables("月").DataCols
        If dc.Expression = "" Then
            dr1(dc.Name) = dr(dc.Name)
        End If
    Next
Next

 

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严谨的判断

 

Dim dc As DataCol  = DataTables("表C").DataCols("c")
Dim pi As System.Reflection.PropertyInfo = dc.Gettype.getproperty("IsTemporary",Reflection.BindingFlags.nonpublic Or Reflection.BindingFlags.Instance)
output.show( pi.getvalue(dc,Nothing))