DualListBox Control.
Author: John McGlothlin
Date 2/13/2003
=================================================================
Rendered control. Has 2 listboxes and 4 buttons. The buttons link to client-side
script that moves the listbox items back and forth. Items are sorted and returned
by ListBox VALUE. If you want to change this to TEXT, you have to modify the JS file.

Now includes setting DataSource/Member info at design-time.

** Only works with one instance of control per Page. **
	You would have to change the naming convention I used. I only needed
	one per Page, so it's not an issue.

** The control in Design time doesn't reflect the items added. ** 
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Usage:

if(!Page.IsPostBack)
{			
    // fill DataSet and Bind to control.
    // DataSource and Members set in VS(can be set here also).
	sqlDataAdapter1.Fill(dataSet21);
	this.DualListBox1.DataSource = dataSet21;
	this.DualListBox1.DataBind();  
}
else
{
	// On PostBack, loop thru both lists
	Label1.Text = "LeftBox Items" + "<br>";
	
	// Left ListBox
	foreach(ListItem li in this.DualListBox1.LeftBoxItems)
	{
		Label1.Text += li.Text + "<br>"; 
	}
	Label1.Text += "<br>";
	Label1.Text += "RightBox Items" + "<br>";
	
	// Right ListBox
	foreach(ListItem li in this.DualListBox1.RightBoxItems)
	{
		Label1.Text += li.Text + "<br>"; 
	}
}
