Check if file exists

exists.js

function doesFileExist(urlToFile)
{
    var xhr = new XMLHttpRequest();
    xhr.open('HEAD', urlToFile, false);
    xhr.send();
     
    if (xhr.status == "404") {
        return false;
    } else {
        return true;
    }
}

////////

var result = doesFileExist("http://www.someplace.com/myimage.png");
 
if (result == true) {
    // yay, file exists!
} else {
    // file does not exist!
}