C# - Execute InsertQuery Command From SqlDataSource In JavaScript

I am using ASP.NET

If I want to execute my Insert command from my SqlDataSource in my code behind I would do this.

SqlDataSource1.Insert()

But how would I be able to do this in JavaScript?

<script type='text/javascript' language="javascript">
function valSubmit() {
//Need to call the Insert Command here!

[Code].....

Where in my code behind can I place the Insert() command to make sure only after my valSubmit() function in JavaScript have executed it will then execute the Insert Command?