.计算属性与方法的区别
- 计算属性是基于它们的依赖进行缓存的
- 方法不存在缓存
.侦听器的应用场景
数据变化时执行异步或开销较大的操作
用法:
var vm = new Vue({el: '#app',
data: {
firstName: 'Jim',lastName: 'Green',fullName: 'Jim Green'},
watch: {
firstName: function(val) {
this.fullName = val +''+ this.lastName;},
lastName: function(val)-{
this.fullName = this.firstName + ''+ val;}
}});