在vue父组件传递数据给子组件时候，通过双向绑定给属性赋值时候，报错如下：Avoid mutating a prop directly since the value will be overwritten whenever the parent ***ponent re-renders. Instead, use a data or ***puted property based on the prop's value. Prop being mutated: "content"
1、报错详情
[Vue warn]: Avoid mutating a prop directly since the value will be overwritten whenever the parent ***ponent re-renders. Instead, use a data or ***puted property based on the prop's value. Prop being mutated: "items_index"
2、错误原因
改动了子组件中引用的父组件的变量，也就是props中的数据
在Vue2中组件props中的数据只能单向流动，即只能从父组件通过组件的DOM属性attribute传递props给子组件，子组件只能被动接收父组件传递过来的数据，并且在子组件中，不能修改由父组件传来的props数据。
3、解决方案avoid mutating a prop directly since the value will be overwritten whenever
不要直接修改从父组件传过
