vue3 封装自定义组件v-model的示例

<template>
	<div class="inline">
		<input :type="password ? 'password' : 'text'" ref="input" @input="handleInput" @blur="handleBlur($event.target.value)" :placeholder="placeholder" />
	</div>
</template>
<script>
export default {
	name: "dg-Input",
	props: {
		type: {
			type: String,
			requided: true,
		},
		placeholder: {
			type: String,
		},
		password: {
			default: false,
		},
		modelValue: [String, Number],
	},
	data() {
		return {};
	},
	computed: {
		nativeInputValue() {
			return this.modelValue === null || this.modelValue === undefined ? "" : String(this.modelValue);
		},
	},
	methods: {
		handleInput(event) {
			let value = event.target.value;
			this.$emit("update:modelValue", value);
			this.$emit("input", value);
			this.$nextTick(this.setNativeInputValue);
		},
		setNativeInputValue() {
			const input = this.$refs.input;
			if (input.value === this.nativeInputValue) return;
			input.value = this.nativeInputValue;
		},

	
	},
	mounted() {
		this.setNativeInputValue();
	},
};
</script>
<style lang="scss" scoped>
.inline {
	display: inline-block;
	input {
		width: 100%;
		height: 100%;
		padding-left: 5px;
	}
}
</style>

<input v-model="test">
<!--上面代码本质上就是下方代码-->
<input :value="test" @input="test = $event.target.value">

<template>
    <div>
        <child v-model="msg" @input="msg = $event.target.value" />
        <!--<child :value="msg" @input="msg = $event.target.value" />-->
    </div>
</template>
<script>
import child from './components/Child.vue'
export default {
    components: {
        child
    },
    data() {
        return {
            msg: ''
        }
    }
}
</script>

<template>
    <input type="text" :value="modelValue" @input="handleInput">
</template>
<script>
export default {
    name: 'Child',
    props:['value'],
    data() {
        return {
            modelValue: this.value
        }
    },
    methods: {
        handleInput(event) {
            this.$emit('input', event)
        }
    }
}

<template>
  <child v-model="msg" />
  <p>{{msg}}</p>
</template>
 
<script lang="ts">
import { defineComponent,ref} from 'vue';
import child from './components/child/index.vue'
 
export default defineComponent({
  name: 'App',
  components:{
    child
  },
  setup(){
    const msg = ref('1')
    return{
      msg
    }
  }
});
</script>

<template>
    <input type="text" :value="modelValue" @input="onInput">
</template>
<script lang="ts">
import {defineComponent} from 'vue'
export default defineComponent({
    name:'ChildInput',
    props:{
        modelValue:{
            type:String
        }
    },
    setup(props, context){
        const onInput = (e: Event) =>{
            context.emit('update:modelValue',e.target.value)
        }
        return{
            onInput
        }
    }
})
</script>