Ajax Editor showing error

<cc1:Editor ID="txtEditor" runat="server"  CssClass="form-control" Width="100%" BackColor="WhiteSmoke" Height="400px" Font-Names="Comic Sans MS"/>

CODE

 protected void btnSubmit_Click(object sender, EventArgs e)
    {
        lblContents.Text = txtEditor.Text;
    }
}

ERROR

Error	21	'AjaxControlToolkit.HTMLEditor.Editor' does not contain a definition for 'Text' and no extension method 'Text' accepting a first argument of type 'AjaxControlToolkit.HTMLEditor.Editor' could be found (are you missing a using directive or an assembly reference?)	C:\Users\migold\Documents\Visual Studio 2013\WebSites\HORNTIMESITE\ComposeMail.aspx.cs	34	38	HORNTIMESITE(1)