(c) 2002 Visual Studio Magazine 
Fawcette Technical Publications

Issue: May 2002
Section: ASP.NET
Author: Dino Esposito

C#	Show or Hide Extra Columns
Listing 1	This procedure handles the user's clicking on the button column to show or hide the extra columns. This code stores the display state of the optional columns in the HasExtraColumns slot in the page's ViewState repository.

void HandleCommands(Object sender, 
DataGridCommandEventArgs e)
{
	if (e.CommandName == "ExpandColumns")
	{
		if (Convert.ToBoolean(ViewState
			["HasExtraColumns"]))
		{
			RemoveExtraColumns();
			ViewState["HasExtraColumns"] = false;
		}
		else
		{
			AddExtraColumns();
			ViewState["HasExtraColumns"] = true;
		}
		grid.DataSource = CreateDataSource();
		grid.DataBind();
	}
}
