主题：求助批量改变字段值设置，大红袍老师已给过思路

datacolchanged事件代码

Dim str As String = ""
Select Case e.DataCol.Name
    Case "档号构成项目","位数","连接符"
        For Each dr As DataRow In e.DataTable.Select("表名 = '" & e.DataRow("表名") & "'")
            If dr.IsNull("档号构成项目") = False Then
                If dr.IsNull("位数") Then
                    str &= "isnull(Convert([" & dr("档号构成项目") & "],'System.String'),'')+"
                Else
                    Dim temp = "substring(isnull(Convert([" & dr("档号构成项目") & "],'System.String'),''),1," & dr("位数") & ")"
                    str &= "substring('" & "".PadLeft(dr("位数"),"0") & "', 1, " & dr("位数") & "-len(" & temp & ")) + " & temp
                    str &= "+"
                End If
               
                If dr.IsNull("连接符") = False Then
                    str &=  "'" & dr("连接符") & "'+"
                End If
               
            End If
        Next
        DataTables(e.DataRow("表名")).DataCols("文件级档号").Expression = str.trim("+")
        If Forms("窗口1").opened Then
            Forms("窗口1").Controls("TextBox1").Text = DataTables(e.DataRow("表名")).Compute("max(文件级档号)")
        End If
End Select