js的一些特性

<script>
window.onload = function(){
var lio = {};
lio.age= '18';
Object.prototype.name = 'anna';
if(!NaN){
for(var i in lio){
if(lio.hasOwnProperty(i)){
console.log('本身属性有:'+i);
}else {
console.log('原型上有属性:'+i);
}
}
}
};
</script>

/**
* 引用传值
*/
function chuanzhi(){
var wife = {
'name' : 'anna',
'age' : 18
};
var lio = wife;
lio.name = 'lio';
console.log(wife.name);
console.log(wife===lio);
}
chuanzhi();

/**
* 对象字面量
*/
function zimianliang(){
var anna = {
'name':'anna',
'age':12,
'hobby':function(num){
console.log(num)
},
'love':[1,2,3,4,5]
};
anna.hobby(521);
anna.love.forEach(function(ele,index,arr){
console.log(ele);
});
anna.love.map(function(ele,index){
console.log(ele);
});
//不改变原来数组
anna.love.filter(function(item){
return (item > 2);
});
//不改变原来数组
anna.love.some(function (item) {
return (item > 2);
});
//不改变原来数组
var ll = anna.love.every(function (item) {
return (item > 2);
});
return ll;
}
console.log(zimianliang());

/**
* 删除以及防止污染全局变量
*/
var global = 'zhende';
function shanchu(){
window.zhendea = 'jiadea';
//意义和上边一样
shuxing = 'jiade';

delete zhendea;
delete shuxing;
delete global;//可以被删除,只是全局的一个属性

console.log(zhendea);//不可以被删除
console.log(global);//不可以被删除
console.log(shuxing.prototype);

}
shanchu();