https://segmentfault.com/q/1010000011682795

 如监听this.$store.state.app.language的值，注意写在method外面
 
watch: {
    '$store.state.app.language': function () {
      //你需要执行的代码
    }
  },
 
 

 computed:
      mapState({ socket: state => state.ws.socket }),


watch: {
socket: {
      handler: function(val) {
        if (this.$store.state.ws.socket.message.state === 'success') {
          this.$notify({
            title: '成功',
            message: '短信发送成功',
            type: 'success',
            duration: 2000
          })
        }
      },
      deep: true
    }
}
 
'$store.state.ws.socket.message.state': function() {
      if (this.$store.state.ws.socket.message.state === 'success') {
        this.$notify({
          title: '成功',
          message: '短信发送成功',
          type: 'success',
          duration: 2000
        })
      }
    }
 
 

如监听this.$store.state.nowCity的值，在watch对象中写
 
watch: {
    '$store.state.nowCity' () {
      //你需要执行的代码
    }
  },