Check url content type with javascript

问题

In order to conserve server resources I'm looking for a way to retrieve the content type of a given url using javascript. It should not download the complete content from the url only the headers. Is this possible with the restrictions javascript has.

回答1:

Make an Ajax call with a head request.

var url = window.location.href;
var xhttp = new XMLHttpRequest();
xhttp.open('HEAD', url);
xhttp.onreadystatechange = function () {
    if (this.readyState == this.DONE) {
        console.log(this.status);
        console.log(this.getResponseHeader("Content-Type"));
    }
};
xhttp.send();

来源：https://stackoverflow.com/questions/24050112/check-url-content-type-with-javascript