extjs中apply和applyIf的用法

Ext.apply = function(object, config, defaults) ...{
        if (defaults) ...{
            Ext.apply(object, defaults);
        }
        if (object && config && typeof config === 'object') ...{
            var i, j, k;
            for (i in config) ...{//复制所有属性
                object[i] = config[i];
            }
            if (enumerables) ...{
                for (j = enumerables.length; j--;) ...{
                    k = enumerables[j];
                    if (config.hasOwnProperty(k)) ...{
                        object[k] = config[k];
                    }
                }
            }
        }
            return object;
};
				

var b1=...{ p1:"p1 value", p2:"p2 value", f1:function()...{alert(this.p2)}};
 

var b2=new Object();
 

b2.p2="b2 value";
 

Ext.apply(b2,b1);

b2.f1();

		

applyIf: function(object, config) ...{
            var property;
            if (object) ...{
                for (property in config) ...{
                    if (object[property] === undefined) ...{//如果object中不含有这个属性，复制属性，否则不复制
                        object[property] = config[property];
                    }
                }
            }
            return object;
        },