关于userData

[b]userData 的容量限制：[/b]

Security Zone Document Limit (KB) Domain Limit (KB)
Local Machine 128 1024
Intranet 512 10240
Trusted Sites 128 1024
Internet 128 1024
Restricted 64 640

/* IE6/7的本地存储可以使用userData来实现。不过userData有一个缺陷：无法跨目录使用。 例如：
www.test.com/a.html
www.test.com/b/b.html
www.test.com/c/c.html
这3个页面，userData数据时独立的，无法共享。

UserData 在XP的存放路径：
C:\Documents and Settings\shawn\UserData
*/
var Userdata = {
    storageObject: null,
    initialize: function() {
        if (!this.storageObject) {
            this.storageObject = document.createElement("div");
            this.storageObject.addBehavior("#default#userData");
            this.storageObject.style.display = "none";
            document.body.appendChild(this.storageObject);
        }
    },
    set: function(key, value) {
        if (!this.storageObject){
            this.initialize();
        }
        this.storageObject.setAttribute(key, value);
        this.storageObject.save("OfflineStorage");
        return value;
    },
    get : function(key){
        if (!this.storageObject){
            this.initialize();
        }
        this.storageObject.load("OfflineStorage");
        return this.storageObject.getAttribute(key);
    },
    del: function(key) {
        if (!this.storageObject){
            this.initialize();
        }
        this.storageObject.removeAttribute(key);
        this.storageObject.save("OfflineStorage");
    }
};