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Javascript turns a JSON string into an instance of a function

I have a bunch of JSON strings returned from an ajax call in a specific format, and when I start converting all of them into my own Javascript object, I begin to wonder if there is an even easier way, since we are talking about Javascript here.

I will have var manyOfThem = [ { name: 'a' }, { name: 'b' }, { name: 'c' } ]; And I would like to easily associate each of these objects with my functions so that I can do things like:

myClass.prototype.doSomething = function() {
  // do something to this.name
};

$.each(manyOfThem, function(index, item) {
  item.doSomething();
});

I think my concern is that I would not want (because its repetitive) to do this:

var myClass = function(item) {
  this.name = item.name;
  // do the same for the rest of item potentially 20 properties
};

var oneOfThem = new myClass(manyOfThem[0]); // I think this is redundant....
oneOfThem.doSomething();

Anyway, if there are reasons (security concerns?) Why I just need to suck them in and do it all manually, please share them, thanks!

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3

, - (. jsfiddle):

var MyClass = function() {};
MyClass.prototype = {
    doSomething: function() {
        alert(this.name);
    }
};


var manyObj = $.map(manyOfThem, function(obj) {
   return $.extend( new MyClass(), obj );
});

, :

manyObj[0].doSomething();  // alert("a")

manyOfThem. ( manyOfThem[0].name = "foo"; manyObj[0], manyObj[0].doSomething(); "a". , :

var manyObj = $.map(manyOfThem, function(obj) {
    function F() {};
    F.constructor = MyClass;
    F.prototype = obj;
    $.extend(F.prototype, new MyClass());
    return new F();
});


manyObj[0].doSomething();  // alert("a")

manyOfThem[0].name = "foo";  // modify the referenced object

manyObj[0].doSomething();  // alert("foo") ..also modifies the behaviour of the instance
+3

var manyOfThem = [ { name: 'a' }, { name: 'b' }, { name: 'c' } ];

function doSomething(){
    console.log(this.name)
}

$.each(manyOfThem, function(index, item) {
  doSomething.call(item);
});

: Fiddle

MyClas,

var manyOfThem = [ { name: 'a' }, { name: 'b' }, { name: 'c' } ];

function MyClass(item){
    $.extend(this, item);
}

MyClass.prototype.doSomething = function(){
    console.log(this.name)
}

$.each(manyOfThem, function(index, item) {
    var obj = new MyClass(item);
    obj.doSomething()
});

: Fiddle

+2

You can do

var myClass = function(item){  
    for( i in item){  
        if (item.hasOwnProperty(i)){
            this[i] = item[i];
        }
    }
};

This should reduce duplicate assignments in the constructor myClass.

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