vue子组件修改父组件传递的变量

子组件不能直接修改父组件变量的值，但是可以通过调用父组件的方法来修改。

实现步骤

在父组件声明变量

export default {data() {return {startTime:"",......},......}
}

在父组件使用子组件并传递数据，修改变量

......
<!-- :startValue传值，@editStartValue修改父组件变量方法editStartTime -->
<date-time-picker :startValue="startTime" @editStartValue="editStartTime">
</date-time-picker>
......

export default {......methods: {editStartTime(val){this.startTime=val;}}
}

在子组件中接收值，并调用父组件方法修改父组件的变量

//接收变量值
props: {startValue: {type: String,default: "",},......
}

//调用父组件方法将值传给父组件
editStartValue() {this.$emit("editStartValue", '2023-08-02 00:00:00');
},

以上步骤只是逻辑步骤和部分代码，以下有完整代码：

父组件

<template><div><!-- 自定义时间组件 --><date-time-picker :particle="particle" :startValue="startTime" :endValue="endTime" @editStartValue="editStartTime" @editEndValue="editEndTime"></date-time-picker></div>
</template><script>
//引入子组件
import dateTimePicker from './date-time-picker.vue';
export default {components: { dateTimePicker },data() {return {//1：时间组件的时间间隔为15分钟，//2：时间组件的时间间隔为1小时，//3：时间组件只能选择日期，不能选择时间，particle:"1",startTime:"",endTime:"",},methods: {editStartTime(val){this.startTime=val;},editEndTime(val){this.endTime=val;},}}
}
</script>

子组件

<template><div><!-- 开始时间-------------------------------------  --><el-time-selectv-model="startTime"style="width: 135px":picker-options="startTimeOptions"placeholder=""prefix-icon="false"@change="startTimeChange"ref="startTime"></el-time-select><!-- 开始日期 --><el-date-pickerv-model="startDate"type="date"ref="startDate"placeholder=""style="width: 135px; margin-left: -135px":picker-options="startDateOptions"@change="startDateChange"value-format="yyyy-MM-dd"></el-date-picker><!-- 选中的开始日期和开始时间展示 --><div@click="handleClickStart"style="width: 200px; margin-left: -135px; display: inline-block"><el-inputv-model="startInput"size="small"ref="startInput":placeholder="placeholderStart"prefix-icon="el-icon-date"></el-input></div><!-- 结束时间------------------------------------- --><el-time-selectv-model="endTime"style="width: 135px":picker-options="endTimeOptions"placeholder=""prefix-icon="false"@change="endTimeChange"ref="endTime"></el-time-select><!-- 结束日期 --><el-date-pickerv-model="endDate"type="date"ref="endDate"placeholder=""style="width: 135px; margin-left: -135px":picker-options="endDateOptions"@change="endDateChange"value-format="yyyy-MM-dd"></el-date-picker><!-- 选中的结束日期和结束时间展示 --><div@click="handleClickEnd"style="width: 200px; margin-left: -135px; display: inline-block"><el-inputv-model="endInput"size="small"ref="endInput":placeholder="placeholderEnd"prefix-icon="el-icon-date"></el-input></div></div>
</template>
<script>
export default {props: {//particle为1时间间隔15分钟，为2时间间隔1小时，为3只能选择日期不能选择时间particle: {type: String,default: "",},startValue: {type: String,default: "",},endValue: {type: String,default: "",},placeholderStart: {type: String,default: "开始时间",},placeholderEnd: {type: String,default: "结束时间",},},watch: {//监听时间粒度的变化，变化时将之前选择的值清空particle(newVal, oldVal) {this.startInput = "";this.endInput = "";(this.startDate = ""),(this.startTime = ""),(this.endDate = ""),(this.endTime = "");},},created(){//页面创建时判断父组件是否传入默认值（格式：yyyy-MM-dd hh:mm:ss）,传入时给日期和时间赋值this.startDate= (this.startInput!=""&&this.startInput.length===19)?this.startInput.substring(0,11):"",this.startTime= (this.startInput!=""&&this.startInput.length===19)?this.startInput.substring(11,16):"",this.endDate= (this.endInput!=""&&this.endInput.length===19)?this.endInput.substring(0,11):"",this.endTime= (this.endInput!=""&&this.endInput.length===19)?this.endInput.substring(11,16):""},data() {return {//父组件初始传默认值，将默认值赋值给展示变量startInput:(this.startValue!=null&&this.startValue!=undefined&&this.startValue.length===19)?this.timeFormat(this.startValue,this.particle):"",endInput:(this.endValue!=null&&this.endValue!=undefined&&this.endValue.length===19)?this.timeFormat(this.endValue,this.particle):"",startDate: "",startTime: "",endDate: "",endTime: "",//时间配置startTimeOptions: {start: "00:00",step: "01:00",end: "23:59",maxTime: "",},endTimeOptions: {start: "00:00",step: "01:00",end: "23:59",minTime: "",},//日期配置（开始时间大于结束时间，结束时间小于开始时间）startDateOptions: {disabledDate: (time) => {if (this.endDate != "") {var now = new Date(this.endDate + " 00:00:00");return time.getTime() > now.getTime();} else {return false;}},},endDateOptions: {disabledDate: (time) => {if (this.startDate != "") {var now = new Date(this.startDate + " 00:00:00");return time.getTime() < now.getTime();} else {return false;}},},};},methods: {//将传入的时间字符串改为对应的格式timeFormat(val,particle) {var str="";if (particle === "3") {str = val.substring(0, 13);var date = new Date(val);var minutes = date.getMinutes();if (minutes / 15 === 0) {str = str + ":00:00";}if (minutes / 15 === 1) {str = str + ":15:00";}if (minutes / 15 === 2) {str = str + ":30:00";}if (minutes / 15 === 3) {str = str + ":45:00";}}if (particle === "2") {str = val.substring(0, 13);str = str + ":00:00";}if (particle === "1") {str = val.substring(0, 11);str = str + "00:00:00"; }return str;},//开始输入框点击事件handleClickStart() {if (this.startInput.length == 19) {this.startDate = this.startInput.substring(0, 11);} else {this.startDate = this.startInput;}this.$refs.startDate.focus();},//结束输入框点击事件handleClickEnd() {if (this.endInput.length == 19) {this.endDate = this.endInput.substring(0, 11);} else {this.endDate = this.endInput;}this.$refs.endDate.focus();},//选择开始日期后调出开始时间startDateChange() {if (this.startTime === "") {this.startInput = this.startDate + " 00:00:00";} else {this.startInput = this.startDate + " " + this.startTime + ":00";}this.editStartValue();if (this.particle != "3") {if (this.particle === "1") {this.startTimeOptions.step = "00:15";}if (this.particle === "2") {this.startTimeOptions.step = "01:00";}if (this.endInput.includes(this.startDate) && this.endTime != "") {this.startTimeOptions.maxTime = this.endTime;}this.$refs.startTime.focus();}},//选择开始时间后赋值给开始输入框startTimeChange() {this.startInput = this.startDate + " " + this.startTime + ":00";this.editStartValue();},//将值传给父组件editStartValue() {this.$emit("editStartValue", this.startInput);},//选择结束日期后调出结束时间endDateChange() {if (this.endTime === "") {this.endInput = this.endDate + " 00:00:00";} else {this.endInput = this.endDate + " " + this.endTime + ":00";}this.editEndValue();if (this.particle != "3") {if (this.particle === "1") {this.endTimeOptions.step = "00:15";}if (this.particle === "2") {this.endTimeOptions.step = "01:00";}if (this.startInput.includes(this.endDate) && this.startTime != "") {this.endTimeOptions.minTime = this.startTime;}this.$refs.endTime.focus();}},//选择结束时间后赋值给结束输入框endTimeChange() {this.endInput = this.endDate + " " + this.endTime + ":00";this.editEndValue();},//将值传给父组件editEndValue() {this.$emit("editEndValue", this.endInput);},},
};
</script>