主题：网页数据下载标题行出现选择框，无法下载

各位老师：

   我在用下面代码进行网页中数据表的下载，并用表头形成临时表的表头，但表头第一列不为空是，可以下载！

Dim web As System.Windows.Forms.WebBrowser = e.Form.controls("webbrowser2").basecontrol
Do Until web.ReadyState = 4 AndAlso web.Document.GetElementById("ctl00_C_gv") IsNot Nothing
    Application.DoEvents
Loop
Dim elems As object = web.Document.GetElementsByTagName("div")
elems = web.Document.GetElementById("ctl00_C_gv").GetElementsByTagName("th")   'ctl00_C_gv
Dim dtb As New DataTableBuilder("录入表")
For i As Integer = 0 To elems.count-1
    dtb.AddDef(elems(i).InnerText,Gettype(String),250)
Next
dtb.Build()
MainTable = Tables("录入表")

DataTables("表B").DataRows.Clear()
elems = web.Document.GetElementById("ctl00_C_gv").GetElementsByTagName("tr")
Dim ndr As Row
For n As Integer = 1 To elems.count - 2
    Dim tds = elems(n).getelementsbytagname("td")
                Dim dr As Row= Tables("表B").AddNew()
    ndr = Tables("录入表").AddNew()
    For tn As Integer = 0 To tds.count -1
        ndr(tn) = tds(tn).InnerText
                    dr(tn) = tds(tn).innerText
    Next
Next

但有些表表头会有个type=checkbox 选择框，便无法下载！

此主题相关图片如下：微信图片_20201201101400.png

无法下载，提示如下：

此主题相关图片如下：微信图片_20201201101406.png

请教各位老师，怎样修改代码，不管有没有选择框都可以下载！

谢谢！