Comparing screen data at client side

Is there any way I can check whether the user has changed any data on the web page between the page load and sav开发者_如何学JAVAe button click. If the user has opened any page to edit some data and clicks the save button without changing any data on the screen then I need to display a message.

Thanks in advance.

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I think setting a flag would be a good idea. Use global selectors to do such a thing.

var changed = false;
$("input").change(function(){
    //something changed
    changed = true;
});

Then if the users leaves the page, check if changed is true

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I think what you are trying to do is check if the form is dirty (i.E. something has changed) and this dirty form plugin might help you.