Persistent Data Storage Object

Hopefully this will be of some use to coders.

Ok, basically it stores data which is persistent. By persistent, I mean that the value will stay forever, so if you were to restart your browser, then the data can be recalled.

This will work in Firefox 2 and IE 6 +.

This is the code, it should be placed into the global header so you have access to it across the whole forum.

<script type="text/javascript">
<!--

function Storage(db){
    this.db = db;
    this.ff = (document.attachEvent)? false : true;
    this.ff2 = (typeof globalStorage != "undefined")? true : false;
    this.host = location.host;
   
    this.gid = function(id){
        return document.getElementById(id);
    }

    if(!this.ff){
        this.storage_objs();
    }
}

Storage.prototype.storage_objs = function(){
    var sobj = document.createElement("input");

    sobj.type = "hidden";
    sobj.id = this.db;
    sobj.className = "userData";
   
    document.body.appendChild(sobj);

    var sheet = document.styleSheets.item(0);

    if(sheet){
        var ud = false;

        for(r = 0; r < sheet.rules.length; r ++){
            if(sheet.rules.item(r).selectorText == ".userData"){
                ud = true;
                break;
            }
        }
   
        if(!ud){
            sheet.addRule(".userData", "behavior: url(#default#userdata)");
        }
    }
}

Storage.prototype.save = function(value){
    if(value){
        if(this.ff && this.ff2){
            var pb_storage = globalStorage[this.host];

            pb_storage[this.db] = value;
        } else if(!this.ff){
            this.storage_objs(this.db);
            this.gid(this.db).setAttribute("pb_pst", value);
            this.gid(this.db).save(this.db);
        }

        return true;
    }

    return false;
}

Storage.prototype.load = function(){
    var value;

    if(this.db){
        if(this.ff && this.ff2){
            var pb_storage = globalStorage[this.host];

            value = pb_storage[this.db];
        } else if(!this.ff){
            this.storage_objs(this.db);
            this.gid(this.db).load(this.db);
            value = this.gid(this.db).getAttribute("pb_pst");
        }
    }

    return value;
}

//-->
</script>

To use it we create a new instance of the Storage object, at the same time we pass a unique name for the storage database.

Example:

var posts = new Storage("posts_db");

We have now created a database where we can store and retrieve values.

To save a value to the database we use the save method like so....

posts.save("5,563");

When run, the string "5,563" will be saved.

At anytime on the forum we can call up this value by calling the load method like so...

posts.load();

Remember, if you haven't created an instance of the object and you wish to load a value, then you will need too do this...

var posts = new Storage("posts_db");

alert(posts.load());

That will alert the posts.

Reason why you might do that is you may be wanting to save a value that is on the main page only (main page header or footer), and then wish to call that value inside a board.

Another good thing is you can create multiple instances of the Storage object so you can store more than 1 item.

Suggestions? Problems? Not understanding?

Post below