javascript - Websocket onmessage 事件不更新组件数据

Question

我正在挂载中设置回调:

data() {
    return {
        code: 'Apple',
    }
},
mounted() {
    console.log(this.code) // prints 'Apple'
    this.$options.sockets.onopen = this.wsOpen();
    this.$options.sockets.onmessage = this.logMessage(msg);
},
methods: {
    logMessage(msg){
        this.code += "\n" + msg.data;
        console.log("this.code: " + this.code);
    },
}

但是它告诉我“msg”未定义。以下内容有效，但是 this.code 超出了范围:

this.$options.sockets.onmessage= function (msg) {
        console.log(msg.data) // this works, msg is not undefined here
        console.log(this.code) // doesnt work, this.code is undefined
    }

我觉得我在做一些愚蠢的事情。

Answer 1

只需将其设置为函数即可。

this.$options.sockets.onmessage = this.logMessage;

代码当前将 onmessage 设置为 this.logMessage(msg) 的结果，并且如错误所述， msg 未定义已安装。