table设置为服务器控件后， 属性丢失

table设置了各列的宽度。如果加上了 runat="server"，则在生成的html里，没有colgroup一节。

<table class="mytable" runat="server" id="Table1" cellpadding="0" cellspacing="0">
<colgroup>
<col width="15%" align="center" />
<col width="10%" />
<col width="15%" />
<col width="10%" />
<col width="15%" />
<col width="10%" />
</colgroup>

MSDN的原话就是

 "A complex table model is not supported. You cannot have an HtmlTable control with nested caption, col, colgroup, tbody, thead, or tfoot elements."