<table cellspacing="1" class="tablesorter">
  <thead>
	<tr>
		<th>&nbsp;</th>
		<th class="header">Case</th>
	</tr>
  </thead>
  <tbody> 	
    <tr class="even">
	<td>test</td>
    </tr>
  </tbody>
</table>

//css
table.tablesorter {margin:10px 0pt 15px; width: 100%; background-color:#CDCDCD; text-align: left;}
table.tablesorter thead tr th, table.tablesorter tfoot tr th {border: 1px solid #FFF; background-color:#F0F0F6; padding: 4px;}
table.tablesorter thead tr .header {background-image: url(/App_Themes/Theme1/Images/bg.gif); background-repeat: no-repeat; background-position: center right; cursor: pointer;}
table.tablesorter tbody td {color: #3D3D3D;	padding: 4px; vertical-align: top; }
table.tablesorter tbody tr.odd td {background-color:#F0F0F6;}
table.tablesorter tbody tr.even td {background-color:#FFFFFF;}
table.tablesorter thead tr .headerSortUp {background-image: url(/App_Themes/Theme1/Images/asc.gif);}
table.tablesorter thead tr .headerSortDown {background-image: url(/App_Themes/Theme1/Images/desc.gif);}
table.tablesorter thead tr .headerSortDown, table.tablesorter thead tr .headerSortUp {background-color: #FFFFEF;}

<table cellspacing="1" class="tablesorter">
  <thead>
	<tr>
		<th>&nbsp;</th>
		<th class="header">Case</th>
	</tr>
  </thead>
  <tbody> 	
    <tr class="even">
	<td>test</td>
    </tr>
  </tbody>
</table>

//css
table.tablesorter thead tr th, table.tablesorter tfoot tr th {
background-color:#F0F0F6;
border:1px solid #FFFFFF;
padding:4px;
}

<table cellspacing="1" class="tablesorter">
				<thead>
					<tr>
						<th>&nbsp;</th>
						<th class="header">Case</th>
					</tr>
				</thead>
				<tbody> 
		
				 <tr class="even">
					<td>test</td>
				</tr>
		
				</tbody>
			</table>

This assumes you're using the jquery tablesorter plugin

Great looking client side sortable html table

C#