Set Col span in grid view row dynamically?

protected void EmployeeGrid_RowCreated(object sender, GridViewRowEventArgs e)
{
    if (e.Row.RowType == DataControlRowType.Header)
    {
        //Creating a gridview object            
        GridView objGridView = (GridView)sender;
 
        //Creating a gridview row object
        GridViewRow objgridviewrow = new GridViewRow(1, 0, DataControlRowType.Header, DataControlRowState.Insert);
 
        //Creating a table cell object
        TableCell objtablecell = new TableCell();
 
        #region Merge cells
 
        //Add a blank cell at the first three cell headers
        //This can be achieved by making the colspan property of the table cell object as 3
        // and the text property of the table cell object will be blank
        //Henceforth, add the table cell object to the grid view row object
        AddMergedCells(objgridviewrow, objtablecell, 3, "Employee Detail", System.Drawing.Color.LightGreen.Name);
 
        //Merge columns d,e (i.e.Address, City, Region, Postal Code, Country) under the column name "Address Details"
        //This can be achieved by making the colspan property of the table cell object as 2
        //and setting it's text to "Address Details" 
        //Henceforth, add the table cell object to the grid view row object
        AddMergedCells(objgridviewrow, objtablecell, 5, "Address Details", System.Drawing.Color.LightSkyBlue.Name);
 
        //Lastly add the gridrow object to the gridview object at the 0th position
        //Because,the header row position is 0.
        objGridView.Controls[0].Controls.AddAt(0, objgridviewrow);
 
        #endregion
    }
}