How do I do this in codebehind (vb.net)??

<table id="tabShowComments" border="2" cellpadding="0" cellspacing="0" width="940px" style="height:auto; border:1px dotted black; border-collapse:collapse;" runat="server">
 
Change The "border:1px dotted black" to change the color to 'white'?? and or turn off the border. But I need the border="2" to remain.
How do I do both, change the color and/or turn on/off border in vb.net codebehind ??
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