vue 组件基础知识剖析
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组件是可复用的Vue实例。
<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <style>
</style> <script src=http://www.0792zz.cn/html/biancheng/yy/2021/1016/"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=http://www.0792zz.cn/html/biancheng/yy/2021/1016/"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=http://www.0792zz.cn/html/biancheng/yy/2021/1016/"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=http://www.0792zz.cn/html/biancheng/yy/2021/1016/"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=http://www.0792zz.cn/html/biancheng/yy/2021/1016/"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=http://www.0792zz.cn/html/biancheng/yy/2021/1016/"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> （编辑：焦作站长网） 【声明】本站内容均来自网络，其相关言论仅代表作者个人观点，不代表本站立场。若无意侵犯到您的权利，请及时与联系站长删除相关内容! |