主题：列标题能否做成下拉框选择

截图说明你的【行类别】的意思。你要做到什么效果？

没看懂你的逻辑。你的逻辑是什么？根据什么规则确定行类别？

你可以判断序号列有没有值，值是不是数字。

Dim dr As DataRow = e.DataRow
Dim dt As Table = Tables(e.DataTable.name)
Dim dic1 As new Dictionary(of String, String)
Dim dic2 As new Dictionary(of String, String)
For Each dc As Col In dt.Cols
    If dic1.ContainsKey(dc.Caption) = False Then
        dic1.Add(dc.Caption, dc.name)
        dic2.Add(dc.name, dc.caption)
    End If
Next

Select Case dic2(e.DataCol.Name)
    Case "项目编码","项目名称","项目特征","单位","工程量","合价"
        If dr.IsNull(dic1("项目编码")) AndAlso dr.IsNull(dic1("单位")) AndAlso dr.IsNull(dic1("合价")) = False AndAlso dr.IsNull(dic1("项目名称")) = False Then
            dr("行类别") = "分部"
        ElseIf dr(dic1("项目编码")).Length > 5 AndAlso dr.IsNull(dic1("项目名称")) = False AndAlso dr.IsNull(dic1("项目特征")) = False AndAlso dr.IsNull(dic1("单位")) = False AndAlso dr.IsNull(dic1("工程量")) = False Then
            dr("行类别") = "清单"
        Else
            dr("行类别") = Nothing
        End If
End Select

Dim dt As Table = Tables("加载表")
Dim dic1 As new Dictionary(of String, String)
For Each dc As Col In dt.Cols
    If dic1.ContainsKey(dc.Caption) = False Then
        dic1.Add(dc.Caption, dc.name)
    End If
Next

For Each dr1 As DataRow In DataTables("加载表").Select("[行类别] is not Null")
    Dim dr2 As DataRow = DataTables("合同清单").AddNew()
    For Each dc As DataCol In DataTables("合同清单").DataCols
        If dic1.ContainsKey(dc.name) Then
            dr2(dc.name) = dr1(dic1(dc.name))
        End If
    Next
Next