navigate away alert without saving modifications
<p>I'm developing a website in php.</p>

<p>I want to show a message something like javascript alert,  when a user tries to edit or add something in a form and tries to navigate to some other section without saving the modification, i want to show a message to them,</p>

<p>that you are about to navigate about from this page, your modifications are not saved, do you want to continue?</p>

<p>how can i do this??</p>

<p>any one have an idea ???please share it with me..</p>

<p>Thanks</p>
