Need to use '@' in javascript within .cshtml page in mvc

Question

I am working with .net MVC4. I am trying to write javascript in .cshtml page. In that I have a function to check valid email id, for that I used regular expression but in that I can't use @ in pattern string.

My code:

@section JSSection{
<script type="text/javascript" language="javascript">

var filter = "@(Html.Raw("^([0-9a-zA-Z]([-.\\w]*[0-9a-zA-Z])*@([0-9a-zA-Z][-\\w]*[0-9a-zA-Z]\\.)+[a-zA-Z]{2,9})$"))";
var filter = "^([0-9a-zA-Z]([-.\\w]*[0-9a-zA-Z])*@([0-9a-zA-Z][-\\w]*[0-9a-zA-Z]\\.)+[a-zA-Z]{2,9})$";

 function isValidEmailAddress(emailAddress)
  {
        var pattern = new RegExp(filter);
        var str=new RegExp("^([0-9a-zA-Z]([-.\\w]*[0-9a-zA-Z])*@([0-9a-zA-Z][-\\w]*[0-9a-zA-Z]\\.)+[a-zA-Z]{2,9})$");
        return pattern.test(emailAddress);

    };
</script>
}

I have problem like:

Like in above image when I use @ in pattern string it will close block early.

Like here when I remove @ then it ends block properly. But I required @ in string what to do?

I also used @@