javascript中client（）兼容性封装

function client() {
    var clientWidth = window.innerWidth || document.documentElement.clientWidth || document.body.clientWidth || 0;
    var clientHeight = window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight || 0;
    var o = {};
    o.width = clientWidth;
    o.height = clientHeight;
    return o;
}