区别：
[]表示是一个数组，如var strs = [‘a‘,‘b‘,‘c‘]。{}表示是一个对象，比如，
var obj = {
name: ‘宙斯‘,
sex: 1
}
如何在数组中删除指定对象呢？？
[
{
"id": 12,
"title": "fdsfsdds",
"markdown": "fsdafafs",
"counttet": "fsdafafs"
},
{
"id": 13,
"title": "fdsfsdds",
"markdown": "fsdafafs",
"counttet": "fsdafafs"
},
{
"id": 14,
"title": "fdsfsdds",
"markdown": "fsdafafs",
"counttet": "fsdafafs"
},
{
"id": 16,
"title": "fdsfsdds",
"markdown": "fsdafafs",
"counttet": "fsdafafs"
},
]
方法： index可以是动态的，这样就能指定删除某一对象
splice(index,1)