在JavaScript中實現命名空間。

(function (){    var namespaceArray = [];    function namespaceObject(name, fullName)    {        this.fullName = fullName;        this.name = name;    };    var namespaceManager =    {        namespaces: namespaceArray        , global: this    };    function using(namespace, action)    {        if (!namespace) throw new Error('namespace 不允許為空白。');        else if (typeof (namespace) != "string") throw new Error('namespace 只能為字串形式。');        else if (namespace.charAt(0) == '.' || namespace.charAt(namespace.length - 1) == '.' || namespace.indexOf("..") != -1)        {            throw new Error("非法的命名空間：" + namespace + "。 ");        }        var parentNS = namespaceArray[namespace];        if (!parentNS)        {            var nss = namespace.split('.'); //- 拆分 namespace            var parentNS = namespaceManager.global; //- 假定上級為全域命名空間            var fullName;            for (var i = 0; i < nss.length; i++)            {                var ns = nss[i];                if (!fullName) fullName = ns;                else fullName = fullName + "." + ns;                var nsObject = parentNS[ns];                if (!nsObject)                {                    nsObject = new namespaceObject(name, fullName);                    parentNS[ns] = nsObject;                }                else if (typeof nsObject != "object") throw new Error(nss.slice(0, i).join('.') + " 非 object 類型的命名空間。");                else nsObject = parentNS[ns];                parentNS = nsObject;            }            namespaceArray[namespace] = parentNS;        }        if (typeof action == "function")        {            action.call(parentNS);        }        if (parentNS !== namespaceManager.global)        {            for (var i in parentNS)            {                if (!namespaceManager.global[i])                    namespaceManager.global[i] = parentNS[i];            }        }        return parentNS;    };    function clearUsing(namespace)    {        var parentNS = namespaceArray[namespace];        if (parentNS)        {            for (var i in parentNS)            {                if (i == "name" || i == "fullName" || typeof parentNS[i] == "namespaceObject") continue;                if (namespaceManager.global[i])                {                    delete namespaceManager.global[i];                }            }        }    }    window.using = using;    window.clearUsing = clearUsing;    window.namespaceManager = namespaceManager;    using("Sofire.Test", function ()    {        this.HelloClass = function ()        {            this.Name = "hello";        };    });    alert(HelloClass);    clearUsing("Sofire.Test");    if (typeof HelloClass != "undefined")    {        alert("Exits");    }    else alert("Not Exits");    using("Sofire.Test", function ()    {        this.HelloClass2 = function ()        {            this.Name2 = "hello2";        }    });    alert(HelloClass);    alert(HelloClass2);})();