组件 基础
1 组件的复用
组件是可复用的Vue实例。
<!DOCTYPE html>
< html >
< head >
< meta charset = "utf-8" >
< style >
</ style >
< script src = "https://cdn.staticfile.org/ vue /2.4.2/vue.min.js" ></ script >
</ head >
< body >
< div id = "app" >
< button-counter ></ button-counter >
< button-counter ></ button-counter >
< button-counter ></ button-counter >
</ div >
< script >
// 定义一个名为 button-counter 的新组件
Vue.component('button-counter', {
data: function () {
return {
count: 0
}
},
template: '< button v-on:click = "count++" >点击了 {{ count }} 次.</ button >'
});
new Vue({ el: '#app' });
</ script >
</ body >
</ html >
注意当点击按钮时，每个组件都会各自独立维护它的count。这里自定义组件的data属性必须是一个函数，每个实例维护一份被返回对象的独立的拷贝。
<!DOCTYPE html>
< html >
< head >
< meta charset = "utf-8" >
< style >
</ style >
< script src = "https://cdn.staticfile.org/vue/2.4.2/vue.min.js" ></ script >
</ head >
< body >
< div id = "app" >
< button-counter ></ button-counter >
< button-counter ></ button-counter >
< button-counter ></ button-counter >
</ div >
< script >
var buttonCounterData = {
count: 0
}
// 定义一个名为 button-counter 的新组件
Vue.component('button-counter', {
data: function () {
return buttonCounterData
},
template: '< button v-on:click = "count++" >点击了 {{ count }} 次.</ button >'
});
new Vue({ el: '#app' });
</ script >
</ body >
</ html >
2 通过 Prop 向子组件传递数据
<!DOCTYPE html>
< html >
< head >
< meta charset = "utf-8" >
< style >
</ style >
< script src = "https://cdn.staticfile.org/vue/2.4.2/vue.min.js" ></ script >
</ head >
< body >
< div id = "app" >
< blog-post title = "My journey with Vue" ></ blog-post >
< blog-post title = "Blogging with Vue" ></ blog-post >
< blog-post title = "Why Vue is so fun" ></ blog-post >
</ div >
< script >
Vue.component('blog-post', {
props: ['title'],
template: '< h3 >{{ title }}</ h3 >'
})
new Vue({ el: '#app' });
</ script >
</ body >
</ html >
这里 <blog-post> 组件就是通过自定义属性 title 来传递数据。
我们可以使用 v-bind 来动态传递prop。
<!DOCTYPE html>
< html >
< head >
< meta charset = "utf-8" >
< style >
</ style >
< script src = "https://cdn.staticfile.org/vue/2.4.2/vue.min.js" ></ script >
</ head >
< body >
< div id = "app" >
< blog-post v-for = "post in posts" v-bind:key = "post.id" v-bind:title = "post.title" ></ blog-post >
</ div >
< script >
Vue.component('blog-post', {
props: ['title'],
template: '< h3 >{{ title }}</ h3 >'
})
new Vue({
el: '#app',
data: {
posts: [
{ id: 1, title: 'My journey with Vue' },
{ id: 2, title: 'Blogging with Vue' },
{ id: 3, title: 'Why Vue is so fun' }
]
}
});
</ script >
</ body >
</ html >
3 单个根元素
每个组件必须只有一个根元素。
<!DOCTYPE html>
< html >
< head >
< meta charset = "utf-8" >
< style >
</ style >
< script src = "https://cdn.staticfile.org/vue/2.4.2/vue.min.js" ></ script >
</ head >
< body >
< div id = "app" >
< blog-post v-for = "post in posts" v-bind:key = "post.id" v-bind:post = "post" ></ blog-post >
</ div >
< script >
Vue.component('blog-post', {
props: ['post'],
template: `
< div class = "blog-post" >
< h3 >{{ post.title }}</ h3 >
< div v-html = "post.content" ></ div >
</ div >
`
})
new Vue({
el: '#app',
data: {
posts: [
{ id: 1, title: 'My journey with Vue', content: 'my journey...' },
{ id: 2, title: 'Blogging with Vue', content: 'my blog...' },
{ id: 3, title: 'Why Vue is so fun', content: 'Vue is so fun...' }
]
}
});
</ script >
</ body >
</ html >
注意到v-bind:post="post"绑定的post是一个对象，这样可以避免了需要通过很多prop传递数据的麻烦。
4 监听子组件事件
<!DOCTYPE html>
< html >
< head >
< meta charset = "utf-8" >
< style >
</ style >
< script src = "https://cdn.staticfile.org/vue/2.4.2/vue.min.js" ></ script >
</ head >
< body >
< div id = "app" >
< div :style = "{fontSize: postFontSize + 'em'}" >
< blog-post v-for = "post in posts"
v-bind:key = "post.id"
v-bind:post = "post"
v-on:enlarge-text = "postFontSize += 0.1" />
</ div >
</ div >
< script >
Vue.component('blog-post', {
props: ['post'],
template: `
< div class = "blog-post" >
< h3 >{{ post.title }}</ h3 >
< button v-on:click = "$emit('enlarge-text')" >放大字体</ button >
< div v-html = "post.content" ></ div >
</ div >
`
})
new Vue({
el: '#app',
data: {
postFontSize: 1,
posts: [
{ id: 1, title: 'My journey with Vue', content: 'my journey...' },
{ id: 2, title: 'Blogging with Vue', content: 'my blog...' },
{ id: 3, title: 'Why Vue is so fun', content: 'Vue is so fun...' }
]
}
});
</ script >
</ body >
</ html >
子组件通过 $emit 方法并传入事件名称来触发一个事件。父组件可以接收该事件。
我们可以使用事件抛出一个值。
<!DOCTYPE html>
< html >
< head >
< meta charset = "utf-8" >
< style >
</ style >
< script src = "https://cdn.staticfile.org/vue/2.4.2/vue.min.js" ></ script >
</ head >
< body >
< div id = "app" >
< div :style = "{fontSize: postFontSize + 'em'}" >
< blog-post v-for = "post in posts"
v-bind:key = "post.id"
v-bind:post = "post"
v-on:enlarge-text = "postFontSize += $event" />
</ div >
</ div >
< script >
Vue.component('blog-post', {
props: ['post'],
template: `
< div class = "blog-post" >
< h3 >{{ post.title }}</ h3 >
< button v-on:click = "$emit('enlarge-text', 0.2)" >放大字体</ button >
< div v-html = "post.content" ></ div >
</ div >
`
})
new Vue({
el: '#app',
data: {
postFontSize: 1,
posts: [
{ id: 1, title: 'My journey with Vue', content: 'my journey...' },
{ id: 2, title: 'Blogging with Vue', content: 'my blog...' },
{ id: 3, title: 'Why Vue is so fun', content: 'Vue is so fun...' }
]
}
});
</ script >
</ body >
</ html >
在父组件中，我们可以通过$event访问到被抛出的这个值。
我们可以在组件上使用v-model。
<!DOCTYPE html>
<html>
<head>
<meta charset= "utf-8" >
<style>
</style>
<script src= "https://cdn.staticfile.org/vue/2.4.2/vue.min.js" ></script>
</head>
<body>
<div id= "app" >
<!-- <input v-model= "searchText" > -->
<input v-bind:value= "searchText" v-on:input= "searchText = $event.target.value" >
<p>{{ searchText }}</p>
</div>
<script>
new Vue({
el: '#app' ,
data: {
searchText: ''
}
});
</script>
</body>
</html>
<!DOCTYPE html>
<html>
<head>
<meta charset= "utf-8" >
<style>
</style>
<script src= "https://cdn.staticfile.org/vue/2.4.2/vue.min.js" ></script>
</head>
<body>
<div id= "app" >
<custom-input v-model= "searchText" ></custom-input>
<custom-input v-bind:value= "searchText" v-on:input= "searchText = $event" ></custom-input>
<p>{{ searchText }}</p>
</div>
<script>
Vue.component( 'custom-input' , {
props: [ 'value' ],
template: `<input v-bind:value= "value" v-on:input= "$emit('input', $event.target.value)" >`
})
new Vue({
el: '#app' ,
data: {
searchText: ''
}
});
</script>
</body>
</html>
最后，注意 解析 DOM 模板时的注意事项 。
以上就是vue 组件基础知识总结的详细内容，更多关于vue 组件的资料请关注服务器之家其它相关文章！
原文链接：https://www.cnblogs.com/gzhjj/p/11769893.html