Get QueryString Variable Value by Javascript

function getQueryVariable(a) {
    var c = window.location.search.substring(1);
    var d = c.split("&");
    for (var b = 0; b < d.length; b++) {
        var e = d[b].split("=");
        if (e[0] == a) {
            return e[1]
        }
    }
}
var StopVideo = getQueryVariable("StopVideo");