Javascript vue.js select中的设置值给出了“未定义”值
当vue组件通过websocket接收更新时,它会为Javascript vue.js select中的设置值给出了“未定义”值,javascript,vue.js,Javascript,Vue.js,当vue组件通过websocket接收更新时,它会为设置新值 相关代码 window.VueBus.$on("updated", (channel, key, value) => { let selfChannel = "model." + self.model + "." + self.pk; if(channel === selfChannel) { if(self.key =
设置新值
相关代码
window.VueBus.$on("updated", (channel, key, value) => {
let selfChannel = "model." + self.model + "." + self.pk;
if(channel === selfChannel) {
if(self.key === key) {
console.log("Set " + key + " to " + value);
self.input.off("change");
console.log("off handler");
self.value = value; // when I set value here error happens
self.$nextTick(() => {
self.input.on("change", this.onInputChange);
console.log("on handler");
self.initInput(true);
});
}
}
});
我增加了手表功能
watch: {
value: function(old, newv) {
console.log('old-new');
console.log(old)
console.log(newv)
}
},
当我打开两个浏览器窗口并在其中一个窗口中进行更改时,这就是它给我的
old-new
19
# it is just an empty string
old-new
undefined
19
但我看到正确的值被传递到组件中
Set recommender_id to 19
off handler # it is required because onInputChange makes requests to server
控制台上的错误
TypeError: Cannot read property 'length' of undefined
这是因为模板中的这一行
<div v-bind:class="{'floating-label-form-group-with-value': value.length > 0}">
在另一个窗口(我在其中进行更改)中,一切正常。解决方案很简单:
v-model on如果缺少匹配项,则将值设置为未定义