The method you are looking for is called Button1_Click in the Details.aspx page (i.e. the one that is being loaded in the RadWindow). You can then obtain the contents of the RadEditor either via its Text property (plain text), or via its Content property (the full HTML content with the markup), for example
RadEditor RadEditor1 = ((RadEditor)DetailsView1.FindControl(
content = RadEditor1.Content;
//send your e-mail with the content string
in the else statement of the button click's method. This is assuming you are using C#, a VB version is available as well, you can examine its counterpart to see how to get the reference.
On the sending of the e-mail - this functionality is out of the scope of our controls, as it requires the developer to setup his/her own SMTP server (or have access to one) so that the message itself can be sent. You can, for example, use the System.Net.Mail
namespace for communicating with the server.
the Telerik team
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