如何为VueJs Props添加多种数据类型？

Question

将不同的值传递给组件时，此错误使我着迷。

Answer 1

这是我找到的解决方案。

props: {
    value: Number | String | Array
 }

或

props: {
    value: [Number,String,Array]
}

Answer 2

如果没有任何类型的麻烦，一般道具会以字符串数组的形式列出：

props: ['title', 'likes', 'isPublished', 'commentIds', 'author']

如果您希望每个道具成为特定类型的值。在这些情况下，您可以将props列为对象，其中属性的名称和值分别包含prop名称和类型：

props: {
    title: String,
    likes: Number,
    isPublished: Boolean,
    commentIds: Array,
    author: Object
}

如果要使用多种类型，请按以下步骤操作：

props: {
    value: [String, Number],
}

Answer 3

正如其他人建议的那样，在vuejs中有两种定义道具的方法：

第一个

//No need to define the type with this one
props: ['myVariable', 'foo', 'something']

第二个

//With this one you can define what type the prop is and other different useful things!
props: {
  myVariable: String, //You can define the type like this
  anyOfTheFollowing: String/Object/Array, //You can also define multiple possible types
  'kebab-case-like': Function, //Since vuejs is still javascript and the property 'props' is actually an object, you can define your props like this for kebab-case. You can also just use camelCase and use the kebab-case version in your template and it will still recognize it
  customOne: MyCustomType, //You can in theory use classes you've defined aswell
  foo: { //This is another way of defining props. Like an object
    type: Number,
    default: 1, //This is why this is mostly used, so you can easily define a default value for your prop in case it isn't defined
  },
  andAnotherOne: {
    type: Array,
    default: () => [], //With Arrays, Objects and Functions you have to return defaults like this since you need to return a new reference to it for it to be used
  },
  requiredOne: {
    type: Object,
    required: true //Another use for this. When it is marked as required and it isn't defined you'll get an error in the console telling you about it
  }
}

IMO我喜欢第二个版本，因为它可以打开的更多，而且我特别喜欢默认属性。

Answer 4

  

带有管道（Number | String）的语法实际上不起作用。这是带有示例的更详细的解决方案：

类型检查，不需要道具

使用以下语法键入检查道具：

props: {
  username: {
    type: [ String, Number ]
  }
}

以下是带有类型检查的属性的实时示例：

Vue.config.devtools = false;
Vue.config.productionTip = false;

Vue.component('test-component', {
  name: 'TestComponent',
  props: {
    username: {
      type: [ String, Number ]
    }
  },
  template: `<div>username: {{ username }}</div>`
});

new Vue({ el: '#app' });

<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.6.10/vue.js"></script>

<div id="app">
  <!-- valid: String -->
  <test-component :username="'user 38'"></test-component>
  
  <!-- valid: Number -->
  <test-component :username="59"></test-component>
  
  <!-- valid: null is valid, it is not required -->
  <test-component :username="null"></test-component>

  <!-- valid: missing property is valid, it is not required -->
  <test-component></test-component>

  <!-- invalid: Array -->
  <test-component :username="['test', 456]"></test-component>
</div>

---

类型检查，必需的道具和自定义验证器

使用以下语法键入所需的属性以及自定义验证器。

props: {
  username: {
    type: [ String, Number ],
    required: true, // optional
    validator: item => item !== '123' // optional
  }
}

这是一个必填属性的实时示例以及一个自定义验证器：

Vue.config.devtools = false;
Vue.config.productionTip = false;

Vue.component('test-component', {
  name: 'TestComponent',
  props: {
    username: {
      type: [ String, Number ],
      required: true,
      validator: item => item !== '123'
    }
  },
  template: `<div>username: {{ username }}</div>`
});

new Vue({ el: '#app' });

<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.6.10/vue.js"></script>

<div id="app">
  <!-- valid: String -->
  <test-component :username="'user 38'"></test-component>
  
  <!-- valid: Number -->
  <test-component :username="59"></test-component>
  
  <!-- invalid: Array -->
  <test-component :username="['test', 456]"></test-component>
  
  <!-- invalid: String, but disallowed by custom validator -->
  <test-component :username="'123'"></test-component>
  
  <!-- invalid: null property, it is required though -->
  <test-component :username="null"></test-component>

  <!-- invalid: missing required prop -->
  <test-component></test-component>
</div>