I am using Infragistics 8.3 and VS 2010 vb

I have a button defined like this:

 <igtbl:UltraGridColumn key="DLTCOLUMN" CellButtonDisplay="Always" 
                        Type="Button" Width="50px">
                         <Header>
                             <RowLayoutColumnInfo OriginX="5" />
                         </Header>
                         <Footer>
                             <RowLayoutColumnInfo OriginX="5" />
                         </Footer>
                    </igtbl:UltraGridColumn>

My previous code worked and looked like this:

<a onclick="if(confirm('Are you sure you want to delete order for customer AAF-MCQUAY CANADA EQ.?','Confirm Order Deletion')){}
else{return false};" 
href="BLOCKED SCRIPT__doPostBack('_ctl2$_ctl6$grdPrevOrds$_ctl2$_ctl1','')">Delete</a>

My question is this:

What is the preferred/supported method to have a client-side confirmation dialog appear?  If cancel then cancel the event otherwise post and run server side ClickCellButton