vue-property-decorator怎么使用

寻技术 VUE 2023年07月11日 112

本文小编为大家详细介绍“vue-property-decorator怎么使用”,内容详细,步骤清晰,细节处理妥当,希望这篇“vue-property-decorator怎么使用”文章能帮助大家解决疑惑,下面跟着小编的思路慢慢深入,一起来学习新知识吧。

我们来看下页面上代码展示:

<template>
  <div>
    foo:{{foo}}
    defaultArg:{{defaultArg}} | {{countplus}}
    <button @click="delToCount($event)">点击del emit</button>
    <HellowWordComponent></HellowWordComponent>
    <button ref="aButton">ref</button>
  </div>
</template>
 
<script lang="ts">
import { Component, Vue, Prop, Emit, Ref } from 'vue-property-decorator';
import HellowWordComponent from '@/components/HellowWordComponent.vue';
 
@Component({
  components: {
    HellowWordComponent,
  },
  beforeRouteLeave(to: any, from: any, next: any) {
    console.log('beforeRouteLeave');
    next();
  },
  beforeRouteEnter(to: any, from: any, next: any) {
    console.log('beforeRouteLeave');
    next();
  },
})
 
export default class DemoComponent extends Vue {
  private foo = 'App Foo!';
 
  private count: number = this.$store.state.count;
 
  @Prop(Boolean) private defaultArg: string | undefined;
 
  @Emit('delemit') private delEmitClick(event: MouseEvent) {}
 
  @Ref('aButton') readonly ref!: HTMLButtonElement;
 
  // computed;
  get countplus () {
    return this.count;
  }
 
  created() {}
 
  mounted() {}
 
  beforeDestroy() {}
 
  public delToCount(event: MouseEvent) {
    this.delEmitClick(event);
    this.count += 1; // countplus 会累加
  }
 
}
 
</script>
 
<style lang="less">
...
</style>

vue-proporty-decorator它具备以下几个装饰器和功能:

  • @Component

  • @Prop

  • @PropSync

  • @Model

  • @Watch

  • @Provide

  • @Inject

  • @ProvideReactive

  • @InjectReactive

  • @Emit

  • @Ref

1.@Component(options:ComponentOptions = {})

@Component
装饰器可以接收一个对象作为参数,可以在对象中声明
components ,filters,directives
等未提供装饰器的选项,也可以声明
computed,watch

registerHooks:
除了上面介绍的将beforeRouteLeave放在Component中之外,还可以全局注册,就是registerHooks

<script lang="ts">
import { Component, Vue } from 'vue-property-decorator';
 
Component.registerHooks([
  'beforeRouteLeave',
  'beforeRouteEnter',
]);
 
@Component
export default class App extends Vue {
  beforeRouteLeave(to: any, from: any, next: any) {
    console.log('beforeRouteLeave');
    next();
  }
 
  beforeRouteEnter(to: any, from: any, next: any) {
    console.log('beforeRouteLeave');
    next();
  }
}
</script>

2.@Prop(options: (PropOptions | Constructor[] | Constructor) = {})

@Prop
装饰器接收一个参数,这个参数可以有三种写法:
  • Constructor
    ,例如
    String,Number,Boolean
    等,指定
    prop
    的类型;
  • Constructor[]
    ,指定
    prop
    的可选类型;
  • PropOptions
    ,可以使用以下选项:
    type,default,required,validator

注意:属性的ts类型后面需要加上

undefined
类型;或者在属性名后面加上!,表示
非null
非undefined

的断言,否则编译器会给出错误提示;
// 父组件:
<template>
  <div class="Props">
    <PropComponent :name="name" :age="age" :sex="sex"></PropComponent>
  </div>
</template>
 
<script lang="ts">
import {Component, Vue,} from 'vue-property-decorator';
import PropComponent from '@/components/PropComponent.vue';
 
@Component({
  components: {PropComponent,},
})
export default class PropsPage extends Vue {
  private name = '张三';
  private age = 1;
  private sex = 'nan';
}
</script>
 
// 子组件:
<template>
  <div class="hello">
    name: {{name}} | age: {{age}} | sex: {{sex}}
  </div>
</template>
 
<script lang="ts">
import {Component, Vue, Prop} from 'vue-property-decorator';
 
@Component
export default class PropComponent extends Vue {
   @Prop(String) readonly name!: string | undefined;
   @Prop({ default: 30, type: Number }) private age!: number;
   @Prop([String, Boolean]) private sex!: string | boolean;
}
</script>

3,@PropSync(propName: string, options: (PropOptions | Constructor[] | Constructor) = {})

@PropSync
装饰器与
@prop
用法类似,二者的区别在于:
  • @PropSync
    装饰器接收两个参数:

propName: string
表示父组件传递过来的属性名;
  • options: Constructor | Constructor[] | PropOptions
    @Prop
    的第一个参数一致;
    @PropSync
    会生成一个新的计算属性。

注意,使用PropSync的时候是要在父组件配合.sync使用的

// 父组件
<template>
  <div class="PropSync">
    <h2>父组件</h2>
    like:{{like}}
    <hr/>
    <PropSyncComponent :like.sync="like"></PropSyncComponent>
  </div>
</template>
 
<script lang='ts'>
import { Vue, Component } from 'vue-property-decorator';
import PropSyncComponent from '@/components/PropSyncComponent.vue';
 
@Component({components: { PropSyncComponent },})
export default class PropSyncPage extends Vue {
  private like = '父组件的like';
}
</script>
 
// 子组件
<template>
  <div class="hello">
    <h2>子组件:</h2>
    <h3>syncedlike:{{ syncedlike }}</h3>
    <button @click="editLike()">修改like</button>
  </div>
</template>
 
<script lang="ts">
import { Component, Prop, Vue, PropSync,} from 'vue-property-decorator';
 
@Component
export default class PropSyncComponent extends Vue {
  @PropSync('like', { type: String }) syncedlike!: string; // 用来实现组件的双向绑定,子组件可以更改父组件穿过来的值
 
  editLike(): void {
    this.syncedlike = '子组件修改过后的syncedlike!'; // 双向绑定,更改syncedlike会更改父组件的like
  }
}
</script>

4.@Model(event?: string, options: (PropOptions | Constructor[] | Constructor) = {})

@Model
装饰器允许我们在一个组件上自定义
v-model
,接收两个参数:
  • event: string
    事件名。
  • options: Constructor | Constructor[] | PropOptions
    @Prop
    的第一个参数一致。

注意,有看不懂的,可以去看下vue官网文档, https://cn.vuejs.org/v2/api/#model

// 父组件
<template>
  <div class="Model">
    <ModelComponent v-model="fooTs" value="some value"></ModelComponent>
    <div>父组件 app : {{fooTs}}</div>
  </div>
</template>
<script lang="ts">
import { Component, Vue } from 'vue-property-decorator';
import ModelComponent from '@/components/ModelComponent.vue';
 
@Component({ components: {ModelComponent} })
export default class ModelPage extends Vue {
  private fooTs = 'App Foo!';
}
</script>
 
// 子组件
<template>
  <div class="hello">
    子组件:<input type="text" :value="checked" @input="inputHandle($event)"/>
  </div>
</template>
 
<script lang="ts">
import {Component, Vue, Model,} from 'vue-property-decorator';
 
@Component
export default class ModelComponent extends Vue {
   @Model('change', { type: String }) readonly checked!: string
 
   public inputHandle(that: any): void {
     this.$emit('change', that.target.value); // 后面会讲到@Emit,此处就先使用this.$emit代替
   }
}
</script>

5,@Watch(path: string, options: WatchOptions = {})

  • @Watch
    装饰器接收两个参数:
  • path: string
    被侦听的属性名;
    options?: WatchOptions={} options
    可以包含两个属性 :

immediate?:boolean
侦听开始之后是否立即调用该回调函数;
deep?:boolean
被侦听的对象的属性被改变时,是否调用该回调函数;

发生在

beforeCreate
勾子之后,
created
勾子之前
<template>
  <div class="PropSync">
    <h2>child:{{child}}</h2>
    <input type="text" v-model="child"/>
  </div>
</template>
 
<script lang="ts">
import { Vue, Watch, Component } from 'vue-property-decorator';
 
@Component
export default class WatchPage extends Vue {
  private child = '';
 
  @Watch('child')
  onChildChanged(newValue: string, oldValue: string) {
    console.log(newValue);
    console.log(oldValue);
  }
}
</script>

6,@Emit(event?: string)

  • @Emit
    装饰器接收一个可选参数,该参数是
    $Emit
    的第一个参数,充当事件名。如果没有提供这个参数,
    $Emit
    会将回调函数名的
    camelCase
    转为
    kebab-case
    ,并将其作为事件名;
  • @Emit
    会将回调函数的返回值作为第二个参数,如果返回值是一个
    Promise
    对象,
    $emit
    会在
    Promise
    对象被标记为
    resolved
    之后触发;
  • @Emit
    的回调函数的参数,会放在其返回值之后,一起被
    $emit
    当做参数使用。
// 父组件
<template>
  <div class="">
    点击emit获取子组件的名字<br/>
    姓名:{{emitData.name}}
    <hr/>
    <EmitComponent sex='女' @add-to-count="returnPersons" @delemit="delemit"></EmitComponent>
  </div>
</template>
 
<script lang="ts">
import { Vue, Component } from 'vue-property-decorator';
import EmitComponent from '@/components/EmitComponent.vue';
 
@Component({
  components: { EmitComponent },
})
export default class EmitPage extends Vue {
  private emitData = { name: '我还没有名字' };
 
  returnPersons(data: any) {
    this.emitData = data;
  }
 
  delemit(event: MouseEvent) {
    console.log(this.emitData);
    console.log(event);
  }
}
</script>
 
// 子组件
<template>
  <div class="hello">
    子组件:
    <div v-if="person">
      姓名:{{person.name}}<br/>
      年龄:{{person.age}}<br/>
      性别:{{person.sex}}<br/>
    </div>
    <button @click="addToCount(person)">点击emit</button>
    <button @click="delToCount($event)">点击del emit</button>
  </div>
</template>
 
<script lang="ts">
import {
  Component, Vue, Prop, Emit,
} from 'vue-property-decorator';
 
type Person = {name: string; age: number; sex: string };
 
@Component
export default class PropComponent extends Vue {
  private name: string | undefined;
 
  private age: number | undefined;
 
  private person: Person = { name: '我是子组件的张三', age: 1, sex: '男' };
 
  @Prop(String) readonly sex: string | undefined;
 
  @Emit('delemit') private delEmitClick(event: MouseEvent) {}
 
  @Emit() // 如果此处不设置别名字,则默认使用下面的函数命名
  addToCount(p: Person) { // 此处命名如果有大写字母则需要用横线隔开  @add-to-count
    return this.person; // 此处不return,则会默认使用括号里的参数p;
  }
 
  delToCount(event: MouseEvent) {
    this.delEmitClick(event);
  }
}
</script>

7,@Ref(refKey?: string)

@Ref
装饰器接收一个可选参数,用来指向元素或子组件的引用信息。如果没有提供这个参数,会使用装饰器后面的属性名充当参数
<template>
  <div class="PropSync">
    <button @click="getRef()" ref="aButton">获取ref</button>
    <RefComponent name="names" ref="RefComponent"></RefComponent>
  </div>
</template>
 
<script lang="ts">
import { Vue, Component, Ref } from 'vue-property-decorator';
import RefComponent from '@/components/RefComponent.vue';
 
@Component({
  components: { RefComponent },
})
export default class RefPage extends Vue {
  @Ref('RefComponent') readonly RefC!: RefComponent;
  @Ref('aButton') readonly ref!: HTMLButtonElement;
  getRef() {
    console.log(this.RefC);
    console.log(this.ref);
  }
}
</script>

8.Provide/Inject ProvideReactive/InjectReactive

@Provide(key?: string | symbol) /

@Inject(options?: { from?: InjectKey, default?: any } | InjectKey)
decorator
@ProvideReactive(key?: string | symbol)
/
@InjectReactive(options?: { from?: InjectKey, default?: any } | InjectKey)
decorator

提供/注入装饰器,
key可以为string或者

symbol类型,

相同点:Provide/ProvideReactive提供的数据,在内部组件使用Inject/InjectReactive都可取到
不同点:

如果提供(
ProvideReactive
)的值被父组件修改,则子组件可以使用
InjectReactive
捕获此修改。
// 最外层组件
<template>
  <div class="">
    <H3>ProvideInjectPage页面</H3>
    <div>
      在ProvideInjectPage页面使用Provide,ProvideReactive定义数据,不需要props传递数据
      然后爷爷套父母,父母套儿子,儿子套孙子,最后在孙子组件里面获取ProvideInjectPage
      里面的信息
    </div>
    <hr/>
    <provideGrandpa></provideGrandpa> <!--爷爷组件-->
  </div>
</template>
 
<script lang="ts">
import {
  Vue, Component, Provide, ProvideReactive,
} from 'vue-property-decorator';
import provideGrandpa from '@/components/ProvideGParentComponent.vue';
 
@Component({
  components: { provideGrandpa },
})
export default class ProvideInjectPage extends Vue {
  @Provide() foo = Symbol('fooaaa');
 
  @ProvideReactive() fooReactive = 'fooReactive';
 
  @ProvideReactive('1') fooReactiveKey1 = 'fooReactiveKey1';
 
  @ProvideReactive('2') fooReactiveKey2 = 'fooReactiveKey2';
 
  created() {
    this.foo = Symbol('fooaaa111');
    this.fooReactive = 'fooReactive111';
    this.fooReactiveKey1 = 'fooReactiveKey111';
    this.fooReactiveKey2 = 'fooReactiveKey222';
  }
}
</script>
 
// ...provideGrandpa调用父母组件
<template>
  <div class="hello">
    <ProvideParentComponent></ProvideParentComponent>
  </div>
</template>
 
// ...ProvideParentComponent调用儿子组件
<template>
  <div class="hello">
    <ProvideSonComponent></ProvideSonComponent>
  </div>
</template>
 
// ...ProvideSonComponent调用孙子组件
<template>
  <div class="hello">
    <ProvideGSonComponent></ProvideGSonComponent>
  </div>
</template>
 
 
// 孙子组件<ProvideGSonComponent>,经过多层引用后,在孙子组件使用Inject可以得到最外层组件provide的数据哦
<template>
  <div class="hello">
    <h4>孙子的组件</h4>
    爷爷组件里面的foo:{{foo.description}}<br/>
    爷爷组件里面的fooReactive:{{fooReactive}}<br/>
    爷爷组件里面的fooReactiveKey1:{{fooReactiveKey1}}<br/>
    爷爷组件里面的fooReactiveKey2:{{fooReactiveKey2}}
    <span >=> fooReactiveKey2没有些key所以取不到哦</span>
  </div>
</template>
 
<script lang="ts">
import {
  Component, Vue, Inject, InjectReactive,
} from 'vue-property-decorator';
 
@Component
export default class ProvideGSonComponent extends Vue {
  @Inject() readonly foo!: string;
 
  @InjectReactive() fooReactive!: string;
 
  @InjectReactive('1') fooReactiveKey1!: string;
 
  @InjectReactive() fooReactiveKey2!: string;
}
</script>
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