It seems it doesn't render the selected rows.

I tried using:

Crawling up the walls, started digging into the code, found out that:

1. This doesn't occurr for all rows, just for the alternate ones. Normal items are rendered properly.
2. The reason is simple: the adapter doesn't render a AspNet-GridView-Selected Class for the alternate ones, in fact, it doesn't give ANY class for the selected one and the one before, and the one after.

this is a piece of the rendered HTML

Before: (row number one selected, all is fine)

 
<tbody>
	<tr class=" AspNet-GridView-Selected ">
		<td><a href="javascript:__doPostBack('GridView1','Select$0')">Select</a></td>
		<td>Sinh</td>
		<td>17416</td>
		<td>31</td>
		<td>1.7943</td>
	</tr>
	<tr class=" AspNet-GridView-Alternate ">
		<td><a href="javascript:__doPostBack('GridView1','Select$1')">Select</a></td>
		<td>Tanh</td>
		<td>17448</td>
		<td>31</td>
		<td>1.7910</td>
	</tr>
	<tr>
		<td><a href="javascript:__doPostBack('GridView1','Select$2')">Select</a></td>
		<td>Truncate</td>
		<td>18233</td>
		<td>31</td>
		<td>1.7139</td>
	</tr>
  

And after - row number 2 (alternate item) chosen:

<tbody>
	<tr>
		<td><a href="javascript:__doPostBack('GridView1','Select$0')">Select</a></td>
		<td>Sinh</td>
		<td>17416</td>
		<td>31</td>
		<td>1.7943</td>
	</tr>
	<tr>
		<td><a href="javascript:__doPostBack('GridView1','Select$1')">Select</a></td>
		<td>Tanh</td>
		<td>17448</td>
		<td>31</td>
		<td>1.7910</td>
	</tr>
	<tr>
		<td><a href="javascript:__doPostBack('GridView1','Select$2')">Select</a></td>
		<td>Truncate</td>
		<td>18233</td>
		<td>31</td>
		<td>1.7139</td>
	</tr>

I continued...

The problem originates in the GetRowClass function in GridViewAdapter.vb, the select-case there doesn't allow for the fact that

 DataControlRowState is actually a bitwise variable enum.

You see:

1    Private Function GetRowClass(ByVal gridView As GridView, ByVal row As GridViewRow) As String
2     Dim className As String = ""
3    
4     Select Case row.RowState
5        Case DataControlRowState.Alternate
6           className += " AspNet-GridView-Alternate "
7           className += gridView.AlternatingRowStyle.CssClass
8        Case DataControlRowState.Edit
9           className += " AspNet-GridView-Edit "
10          className += gridView.EditRowStyle.CssClass
11       Case DataControlRowState.Insert
12          className += " AspNet-GridView-Insert "
13       Case DataControlRowState.Selected, DataControlRowState.Selected Or DataControlRowState.Alternate
14          className += " AspNet-GridView-Selected "
15          className += gridView.SelectedRowStyle.CssClass
16    End Select
17   
18    Return className
19   End Function