問題描述

開發專案時經常用到客戶端檢測，
本文為閱讀了《JavaScript高階程式設計》後的筆記，方便今後檢視。

物件編寫

/**
 * 匿名函式
 * @type {{engine}} Clinet接受匿名函式返回值
 */
var client = function(){
    //呈現引擎，預設各個引擎為0，如果檢測到了當前瀏覽器的呈現引擎，就將該引擎的版本號寫入對應的位置
    //ver為當前呈現引擎的完整版本
    var engine = {
        ie: 0,
        gecko: 0,
        webkit: 0,
        khtml: 0,
        opera: 0
 
,
        //具體版本號
        ver: null
    };
    //browser為瀏覽器
    var browser = {
        ie: 0,
        firefox: 0,
        safari: 0,
        konq: 0,
        opera: 0,
        chrome: 0,
        //具體版本號
        ver: null
    };
    var system = {
        //windows、mac、linux
        win: false,
        mac: false
 
,
        xll: false,

        //移動裝置
        iphone: false,
        ipod: false,
        ipad: false,
        ios: false,
        android: false,
        nokiaN: false,
        winMobile: false,

        //遊戲系統
        wii: false,
        ps: false
    };


    var ua = navigator.userAgent;
    if(window.opera){
        //檢測Opera
 

        engine.ver = browser.ver = window.opera.version();
        engine.opera = browser.opera = parseFloat(engine.ver);
    }else if(/AppleWebKit\/(\S+)/.test(ua)){
        //檢測WebKit
        engine.ver = RegExp["$1"];
        engine.webkit = parseFloat(engine.ver);

        //確定是Chrome還是Safari
        if(/Chrome\/(\S+)/.test(ua)){
            //檢測是否是Chrome
            browser.ver = RegExp["$1"];
            browser.chrome = parseFloat(browser.ver);
        }else if(/Version\/(\S+)/.test(ua)){
            //檢測是否是safari
            browser.ver = RegExp["$1"];
            browser.safari = parseFloat(browser.ver);
        }else{
            //近似的確定版本號
            var safariVersion = 1;
            if (engine.webkit < 100){
                safariVersion = 1;
            } else if (engine.webkit < 312){
                safariVersion = 1.2;
            } else if (engine.webkit < 412){
                safariVersion = 1.3;
            } else {
                safariVersion = 2;
            }
            browser.safari = browser.ver = safariVersion;
        }
    }else if(/KHTML\/(\S+)/.test(ua) || /Konqueror\/([^;]+)/.test(ua)){
        //檢測KHTML
        engine.ver = browser.ver = RegExp["$1"];
        engine.khtml = browser.konq = parseFloat(engine.ver);
    }else if(/rv:([^\)]+)\) Gecko\/\d{8}/.test(ua)){
        //檢測Gecko
        engine.ver = RegExp["$1"];
        engine.gecko = parseFloat(engine.ver);

        //確定是不是Firefox瀏覽器
        if (/Firefox\/(\S+)/.test(ua)){
            browser.ver = RegExp["$1"];
            browser.firefox = parseFloat(browser.ver);
        }
    }else if(/MSIE ([^;]+)/.test(ua)){
        //檢測IE
        engine.ver = browser.ver = RegExp["$1"];
        engine.ie = browser.ie = parseFloat(engine.ver);
    }
    //檢測瀏覽器
    browser.ie = engine.ie;
    browser.opera = engine.opera;


    //檢測平臺
    var p = navigator.platform;
    system.win = p.indexOf("Win") == 0;
    system.mac = p.indexOf("Mac") == 0;
    system.xll = (p == "Xll") || (p.indexOf("Linux") == 0);

    //檢測Windows作業系統版本
    if(system.win){
        if(/Win(?:dows )?([^do]{2})\s?(\d+\.\d+)?/.test(ua)){
            if (RegExp["$1"] == "NT"){
                switch(RegExp["$2"]){
                    case "5.0":
                        system.win = "2000";
                        break;
                    case "5.1":
                        system.win = "XP";
                        break;
                    case "6.0":
                        system.win = "Vista";
                        break;
                    case "6.1":
                        system.win = "7";
                        break;
                    default:
                        system.win = "NT";
                        break;
                }
            } else if (RegExp["$1"] == "9x"){
                system.win = "ME";
            } else {
                system.win = RegExp["$1"];
            }
        }
    }

    //檢測移動裝置
    system.iphone = ua.indexOf("iPhone") > -1;
    system.ipod = ua.indexOf("iPod") > -1;
    system.ipad = ua.indexOf("iPad") > -1;
    system.nokiaN = ua.indexOf("NokiaN") > -1;

    //檢測windows mobile
    if(system.win == "CE"){
        system.winMobile = system.win;
    }else if(system.win == "Ph"){
        if(/Windows Phone OS (\d+.\d+)/.test(ua)){;
            system.win = "Phone";
            system.winMobile = parseFloat(RegExp["$1"]);
        }
    }

    //檢測ios版本
    if(system.mac && ua.indexOf("Mobile") > -1){
        if (/CPU (?:iPhone )?OS (\d+_\d+)/.test(ua)){
            system.ios = parseFloat(RegExp.$1.replace("_", "."));
        } else {
            system.ios = 2;  //不能真正檢測出來，所以只能猜測
        }
    }

    //檢測Android版本
    if (/Android (\d+\.\d+)/.test(ua)){
        system.android = parseFloat(RegExp.$1);
    }

    //檢測遊戲系統
    system.wii = ua.indexOf("wii") > -1;
    system.ps = /playstation/i.test(ua);


    return {
        engine: engine,
        browser: browser,
        system: system
    };
}();