angularjs - How to check webpage is available or not using javascript -

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i want make web page request if web page available. have written app using angularjs + javascript. there way determine whether webpage available or not using javascript ?

if page in question on different origin, can't without using server somewhere or relying on other page implementing cross-origin resource sharing , supporting origin, because of same origin policy.

if page in question on same origin, can ajax call query it:

var xhr = new xmlhttprequest(); xhr.open("head", url); xhr.onreadystatechange = function() {     if (xhr.readystate == 4) {         if (xhr.status == 200) {             // worked         } else {             // didn't         }     } }; xhr.send();

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