In ASP. net2.0, how does one set the gridview to merge rows or columns?

This. gridview1.datasource = DT;
This. gridview1.databind ();

//************************************** * ****** Determine before Data Binding
Tablecell oldtc = gridview1.rows [0]. cells [0];
For (INT I = 1; I <gridview1.rows. Count; I ++)
{
Tablecell Tc = gridview1.rows [I]. cells [0];
If (oldtc. Text = tc. text)
{
TC. Visible = false;
If (oldtc. rowspan = 0)
{
Oldtc. rowspan = 1;
}
Oldtc. rowspan ++;
Oldtc. verticalalign = verticalalign. Middle;

}
Else
{
Oldtc = tc;
}
}

//************************************** ASPX page.

<Asp: gridview id = "gridview1" runat = "server" autogeneratecolumns = "false" onrowcreated = "gridview1_rowcreated">
<Columns>
<Asp: boundfield datafield = "category" headertext = "category">
<Itemstyle cssclass = "namea" horizontalalign = center width = "130px"/>
</ASP: boundfield>

</Columns>
</ASP: gridview>

// Note: bind columns to merged columns.