h5判断是什么系统

  function detect(){
        var equipmentType = "";
        var agent = navigator.userAgent.toLowerCase();
        var android = agent.indexOf("android");
        var iphone = agent.indexOf("iphone");
        var ipad = agent.indexOf("ipad");
        if(android != -1){
            equipmentType = "android";
        }
        if(iphone != -1 || ipad != -1){
            equipmentType = "ios";
        }
        return equipmentType;
    }