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Vue's template syntax

 HTML-based templating syntax is used in Vue.js, which allows developers to declaratively bind the DOM to the underlying data of a Vue instance. So all Vue.js templates are valid HTML that can be parsed by spec-compliant browsers and HTML parsers. Under the hood, Vue compiles templates into virtual DOM render functions. Combined with a reactive system, Vue can intelligently calculate the minimum number of component re-renders to minimize the number of operations on the DOM.Template syntax in Vue is divided into two categories: interpolation syntax and directive syntax.

Interpolation syntax:

  • Function: used to parse the content of the tag body;
  • Writing: {{? }},? It is a js expression and can directly read all attributes in data.

for example:

        <div id="box1">
            <p>{{hobby}}</p>
        </div>
        <script>
            Vue.config.devtools = true;
            Vue.config.productionTip=false;
            const x=new Vue({
                el:"#box1",
                data:{
                    hobby:"swim"
                },
            })

Command syntax:

  • Function: used to parse tags (including: tag attributes, tag body content, binding events, etc.);

  • Usage example: v-bind: attribute = "xxx" or abbreviated as : attribute = "xxx", xxx is a js expression.

for example:

        <div id="box1">
            <p>{{hobby}}</p>
            <p v-bind:arr="hobby">111</p>
        </div>
        <script>
            Vue.config.devtools = true;
            Vue.config.productionTip=false;
            const x=new Vue({
                el:"#box1",
                data:{
                    hobby:"swim"
                },
            })

v-model (two-way binding): data can flow not only from data to page, but also from page to data.

  • Two-way binding is generally applied to form elements (such as: input, select...)
        <div id="box1">
            <p>{{hobby}}</p>
            <p v-bind:arr="hobby">111</p>
            <input type="text" v-model:value="Inputvalue">
            <input type="text"  v-bind:value="Inputvalue">
        </div>
        <script>
            Vue.config.devtools = true;
            Vue.config.productionTip=false;
            const x=new Vue({
                el:"#box1",
                data:{
                    hobby:"swim",
                    Inputvalue:"666"
                },
            })

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