对于表单大家都很熟悉,v-model 大家也很喜欢,他确实很方便。那么他是怎么实现的呢, 其实他是一个语法糖, v-model 干了 两件事 下面以 input 为例
<input type="text" v-bind:value='message' @input='message = $event.target.value'>
等价于
<input type="text" v-model='message'>
对于自定义组件,我们也要实现双向绑定,对于可编辑div大家都了解,接下来我们来实现可编辑div的双向绑定
子组件:ContentEditable
<template>
<div
class="edit-div"
v-html="innerText"
:contenteditable="canEdit"
@focus="isLocked = true"
@blur="isLocked = false"
@input="changeText"
placeholder="请输入审批意见(必填)"
></div>
</template>
<script>
export default {
name: "ContentEditable",
props: {
value: {
type: String,
default: ""
},
canEdit: {
type: Boolean,
default: true
}
},
data() {
return {
innerText: this.value,
isLocked: false
};
},
watch: {
value() {
if (!this.isLocked || !this.innerText) {
this.innerText = this.value;
}
}
},
methods: {
changeText() {
this.$emit("input", this.$el.innerHTML);
}
}
};
</script>
<style lang="scss">
.edit-div {
width: 100%;
height: 100%;
overflow: auto;
word-break: break-all;
outline: none;
user-select: text;
white-space: pre-wrap;
text-align: left;
&[contenteditable="true"] {
&:empty:before {
content: attr(placeholder);
display: block;
color: #ccc;
}
}
}
</style>
调用:
<ContentEditable v-model="text" />