js 判断 ?wifi ?and 流量

var connection = navigator.connection || navigator.mozConnection || navigator.webkitConnection || { tyep: ‘unknown‘ };var type_text = [‘unknown‘, ‘ethernet‘, ‘wifi‘, ‘2g‘, ‘3g‘, ‘4g‘, ‘none‘];alert(connection.type);var re_el = document.getElementById("re");var btn_el = document.getElementById("btn");function get_status() { ???if (typeof (connection.type) == "number") { ???????connection.type_text = type_text[connection.type]; ???} else { ???????connection.type_text = connection.type; ???} ???if (typeof (connection.bandwidth) == "number") { ???????if (connection.bandwidth > 10) { ???????????connection.type = ‘wifi‘; ???????} else if (connection.bandwidth > 2) { ???????????connection.type = ‘3g‘; ???????} else if (connection.bandwidth > 0) { ???????????connection.type = ‘2g‘; ???????} else if (connection.bandwidth == 0) { ???????????connection.type = ‘none‘; ???????} else { ???????????connection.type = ‘unknown‘; ???????} ???} ???var html = ‘Type : ‘ + connection.type_text; ???html += ‘Bandwidth : ‘ + connection.bandwidth; ???html += ‘isOnline : ‘ + navigator.onLine; ???re_el.innerHTML = html;}btn_el.onclick = function () { ???re_el.innerHTML = ‘Waiting...‘; ???get_status();}