The following string contains the serialize data of a form. I want to include session_id() in the same string, so how can I include something like session_id=session_id(); in it? Thanks.

string = '&' + $('#new_form').serialize();

Inside your form tag u can add hidden input element.

<form>
<input type='hidden' name='session_id' value=<?=session_id()?> >
<!-- your other form elements -->
</form>

Now your jquery will automatically add the session_id

I hope this will help :)

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