Javascript String render(obj)

'use strict';//from w ww. jav a2s .  c  o m

String.prototype.render = function(obj) {
    return this.replace(/\{(\w+)\}/g, function(r, e) {
        return obj[e];
    });
};

String.prototype.render = function(obj) {
    str = this;//  w ww  .j  av  a 2  s.  c o  m
    for (var key in obj) {
        var reg = new RegExp('\\$\\{' + key + '}');
        str = str.replace(reg, obj[key]);
    }
    return str;
}
var greeting = 'my name is ${name},age ${age}';
var result = greeting.render({
    name: 'XiaoMing',
    age: 11
});
console.log(result);