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  • Handlebars的使用方法文档整理(Handlebars.js)

    Handlebars是一款很高效的模版引擎,提供语意化的模版语句,最大的兼容Mustache模版引擎, 提供最大的Mustache模版引擎兼容, 无需学习新语法即可使用;

    Handlebars.js和Mustache 的区别

    目前版本为 2.0.0, 无压缩的情况下目测是 3000行源代码,约 200kb;

    下面这个是基本的模版表达式,
    其中  {{  和  }}  之间为handlerbars的变量; 
    <div class="entry">
  <h1>{{title}}</h1>
  <div class="body">
    {{body}}
  </div>
</div>
    查看更多表达式的用法
    把数据放到自己定义的 <script> 标签中;
    <script id="entry-template" type="text/x-handlebars-template">
  template content
</script>

    编译模版

    使用 Handlebars.compile 进行编译模版;
    var source   = $("#entry-template").html();
var template = Handlebars.compile(source);
    智能编译模版(在移动端也能运行哦么么哒)
    更多有关预编译的链接(Precompilation)


    生成html代码

    通过上面的模版和数据混合编译后的结果: 
    var context = {title: "标题", body: "我是字符串!"}
var html    = template(context);
    JS生成的结果如下:
    <div class="entry">
  <h1>标题</h1>
  <div class="body">
   我是字符串!
  </div>
</div>
    更多template选项


    //代码如下

    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>test</title>
</head>
<body>

<script src="http://libs.baidu.com/jquery/1.9.0/jquery.js"></script>
<script src="http://cdn.madebyglutard.com/libs/handlebars.js/2.0.0/handlebars.js"></script>

<div id="div1"></div>
<script id="entry-template" type="text/x-handlebars-template">    
    <div class="entry">
      <h1>{{title}}</h1>
      <div class="body">
        {{body}}
      </div>
    </div>
</script>
<script>
    //JS代码
    var source   = $("#entry-template").html();
    var template = Handlebars.compile(source);
    
    var context = {title: "标题", body: "我是字符串!"}
    var html    = template(context);
    document.getElementById("div1").innerHTML = html;
</script>

</body>
</html>
    //模版的代码和JS的代码如防止HTML被转义的方法;
    {{ }}和 {{{}}}和区别就是, 如果你不希望变量里面的字符串被转义就使用{{{ }}}对变量进行处理;
    <div class="entry">
  <h1>{{title}}</h1>
  <div class="body">
    {{{body}}}
  </div>
</div>
    数据如下：
    {
  title: "All about <p> Tags",
  body: "<p>This is a post about &lt;p&gt; tags</p>"
}
    定义的Helper如下 
    Handlebars.registerHelper('link', function(text, url) {
      text = Handlebars.Utils.escapeExpression(text);
      url  = Handlebars.Utils.escapeExpression(url);
    
      var result = '<a href="' + url + '">' + text + '</a>';
    
      return new Handlebars.SafeString(result);
    });
    渲染以后的结果如下：
    <div class="entry">
  <h1>All About &lt;p&gt; Tags</h1>
  <div class="body">
    <p>This is a post about &lt;p&gt; tags</p>
  </div>
</div>

     
    //代码如下:

    <!    DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>test</title>
</head>
<body>

<script src="http://libs.baidu.com/jquery/1.9.0/jquery.js"></script>
<script src="http://cdn.madebyglutard.com/libs/handlebars.js/2.0.0/handlebars.js"></script>

<div id="div2"></div>

<script id="entry-template1" type="text/x-handlebars-template">    
    <div class="entry">
      <h1>{{title}}</h1>
      <div class="body">
        {{{body}}}
      </div>
    </div>
</script>

<script>
    Handlebars.registerHelper('link', function(text, url) {
      text = Handlebars.Utils.escapeExpression(text);
      url  = Handlebars.Utils.escapeExpression(url);
    
      var result = '<a href="' + url + '">' + text + '</a>';
    
      return new Handlebars.SafeString(result);
    });
    var source   = $("#entry-template1").html();
    var template = Handlebars.compile(source);
    var context = {
      title: "All about <p> Tags",
      body: "<p>This is a post about &lt;p&gt; tags</p>"
    };
    var html    = template(context);
    document.getElementById("div2").innerHTML = html;
</script>
</body>
</html>

    Handlerbars的自定义表达式

    块表达式允许你定义 helpers 生成自定义的HTML,下面这个是JS的模版; 
    {{#list people}}{{firstName}} {{lastName}}{{/list}}
    如果你使用下面的数据:
    {
  people: [
    {firstName: "Yehuda", lastName: "Katz"},
    {firstName: "Carl", lastName: "Lerche"},
    {firstName: "Alan", lastName: "Johnson"}
  ]
}
    在JS里面定义这个helper;
    Handlebars.registerHelper('list', function(items, options) {
  var out = "<ul>";

  for(var i=0, l=items.length; i<l; i++) {
    out = out + "<li>" + options.fn(items[i]) + "</li> " ;       /*options.fn相当于一个编译的函数*/
  }  

  return out + "</ul>";
});
    执行以后的结果是:
    <ul>
  <li>Yehuda Katz</li>
  <li>Carl Lerche</li>
  <li>Alan Johnson</li>
</ul>
    自定义块表达式还有很多别的特性, 比如可以直接使用 IF 和 ELSE；
    Learn More: Block Helpers
     
    //代码如下：
    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>test</title>
</head>
<body>

<script src="http://libs.baidu.com/jquery/1.9.0/jquery.js"></script>
<script src="http://cdn.madebyglutard.com/libs/handlebars.js/2.0.0/handlebars.js"></script>


<div id="div3"></div>
<script id="entry-template2" type="text/x-handlebars-template">    
    {{! 这个是模版的注释 }}
    {{#list people}}{{firstName}} {{lastName}}{{/list}}
</script>
<script>
    Handlebars.registerHelper('list', function(items, options) {
      var out = "<ul>";
    
      for(var i=0, l=items.length; i<l; i++) {
        out = out + "<li>" + options.fn(items[i]) + "</li> " ;       /*options.fn相当于一个编译的函数*/
      }  
    
      return out + "</ul>";
    });
    
    var source   = $("#entry-template2").html();
    var template = Handlebars.compile(source);
    var context = {
      people: [
        {firstName: "Yehuda", lastName: "Katz"},
        {firstName: "Carl", lastName: "Lerche"},
        {firstName: "Alan", lastName: "Johnson"}
      ]
    };
    var html    = template(context);
    document.getElementById("div3").innerHTML = html;
</script>


</body>
</html>

     

    Handlebars次级数据的渲染

    Handlebars支持简单的下级对象获取和上级对象获取, 跟 Mustache一样样的. 
    <p>{{name}}</p>
    Handlebars 也支持多层次的数据展示, 模版如下.
    <div class="entry">
  <h1>{{title}}</h1>
  <h2>By {{author.name}}</h2>

  <div class="body">
    {{body}}
  </div>
</div>
    下面这个是要使用到的Handlebars的 数据;
    var context = {
  title: "My First Blog Post!",
  author: {
    id: 47,
    name: "Yehuda Katz"
  },
  body: "My first post. Wheeeee!"
};
    代码如下：
    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>test</title>
</head>
<body>

<script src="http://libs.baidu.com/jquery/1.9.0/jquery.js"></script>
<script src="http://cdn.madebyglutard.com/libs/handlebars.js/2.0.0/handlebars.js"></script>


<div id="div4">
</div>
<script id="entry-template3" type="text/x-handlebars-template">    
    <div class="entry">
      <h1>{{title}}</h1>
      <h2>By {{author.name}}</h2>
    
      <div class="body">
        {{body}}
      </div>
    </div>
</script>
<script>
    var source   = $("#entry-template3").html();
    var template = Handlebars.compile(source);
    var context = {
      title: "My First Blog Post!",
      author: {
        id: 47,
        name: "Yehuda Katz"
      },
      body: "My first post. Wheeeee!"
    };
    var html    = template(context);
    document.getElementById("div4").innerHTML = html;
</script>


</body>
</html>
    Handlebars 可以迭代Object对象(纯对象或者数组); 在模版中的../是对象的父级;
    <h1>Comments</h1>

<div id="comments">
  {{#each comments}}
  <h2><a href="/posts/{{../permalink}}#{{id}}">{{title}}</a></h2>
  <div>{{body}}</div>
  {{/each}}
</div>
    下面展示的name都是同样的东西;
    <p>{{./name}} or {{this/name}} or {{this.name}}</p>


    Handlebars模版中的注释可以使用 {{!-- --}} 或者 {{! }}或者 <!-- -->.

    可以把模版专用的注释写在模版文件里面么么哒. 提高代码的可读性, 这个也算是最佳实践吧; 
    <div class="entry">
  {{!-- only output this author names if an author exists --}}
  {{#if author}}
    <h1>{{firstName}} {{lastName}}</h1>
  {{/if}}
</div>
    {{!-- --}}和{{! }}的注释不会出现在生成的代码中; 如果使用 <!-- --> 注释的代码会出现在生成的代码中;
    <div class="entry">
  {{! This comment will not be in the output }}
  <!-- This comment will be in the output -->
</div>


    自定义标签(Helpers)

    Handlebars的自定义标签可以使用在Handlebars模版的任何地方,必须使用 Handlebars.registerHelper注册到即可; 上代码: 
    <div class="post">
  <h1>By {{fullName author}}</h1>
  <div class="body">{{body}}</div>

  <h1>Comments</h1>

  {{#each comments}}
  <h2>By {{fullName author}}</h2>
  <div class="body">{{body}}</div>
  {{/each}}
</div>
    这个是要用到的data
    var context = {
  author: {firstName: "Alan", lastName: "Johnson"},
  body: "I Love Handlebars",
  comments: [{
    author: {firstName: "Yehuda", lastName: "Katz"},
    body: "Me too!"
  }]
};

//就是下面这个helper提供了模版中的自定义标签;
Handlebars.registerHelper('fullName', function(person) {
  return person.firstName + " " + person.lastName;
});
    生成的结果如下:
    <div class="post">
  <h1>By Alan Johnson</h1>
  <div class="body">I Love Handlebars</div>

  <h1>Comments</h1>

  <h2>By Yehuda Katz</h2>
  <div class="body">Me Too!</div>
</div>

    代码如下： 
    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>test</title>
</head>
<body>

<script src="http://libs.baidu.com/jquery/1.9.0/jquery.js"></script>
<script src="http://cdn.madebyglutard.com/libs/handlebars.js/2.0.0/handlebars.js"></script>


<div id="div5"></div>
<script id="entry-template5" type="text/x-handlebars-template">    
    <div class="post">
      <h1>By {{fullName author}}</h1>
      <div class="body">{{body}}</div>
    
      <h1>Comments</h1>
    
      {{#each comments}}
      <h2>By {{fullName author}}</h2>
      <div class="body">{{body}}</div>
      {{/each}}
    </div>
</script>
<script>
    var context = {
      author: {firstName: "Alan", lastName: "Johnson"},
      body: "I Love Handlebars",
      comments: [{
        author: {firstName: "Yehuda", lastName: "Katz"},
        body: "Me too!"
      }]
    };
    
    //就是下面这个helper提供了模版中的自定义标签;
    Handlebars.registerHelper('fullName', function(person) {
      return person.firstName + " " + person.lastName;
    });
    
    var source   = $("#entry-template5").html();
    var template = Handlebars.compile(source);
    var html    = template(context);
    document.getElementById("div5").innerHTML = html;
</script>


</body>
</html>
     
     

    在自定义标签的Helper可以使用this, this是当前的对象; 
    <ul>
  {{#each items}}
  <li>{{agree_button}}</li>
  {{/each}}
</ul>
    这个是填充的数据和定义的Helpers:
    var context = {
  items: [
    {name: "Handlebars", emotion: "love"},
    {name: "Mustache", emotion: "enjoy"},
    {name: "Ember", emotion: "want to learn"}
  ]
};

Handlebars.registerHelper('agree_button', function() {
  var emotion = Handlebars.escapeExpression(this.emotion),
      name = Handlebars.escapeExpression(this.name);

  return new Handlebars.SafeString(
    "<button>I agree. I " + emotion + " " + name + "</button>"
  );
});
    生成的结果如下:
    <ul>
  <li><button>I agree. I love Handlebars</button></li>
  <li><button>I agree. I enjoy Mustache</button></li>
  <li><button>I agree. I want to learn Ember</button></li>
</ul>
    如果你希望你返回的HTML代码不被转义, 就要在定义的Helper中返回 new Handlebars.SafeString;
    return new Handlebars.SafeString(代码)


    自定义标签(Helpers)的更多信息;

    Handlebars 提供 if 在模版中进行简单的逻辑处理; 以及迭代处理的标签 each .
    自定义helper的更多信息
     
    //例子代码段:
    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>test</title>
</head>
<body>

<script src="http://libs.baidu.com/jquery/1.9.0/jquery.js"></script>
<script src="http://cdn.madebyglutard.com/libs/handlebars.js/2.0.0/handlebars.js"></script>



<div id="div6"></div>
<script id="entry-template6" type="text/x-handlebars-template">    
    {{#list people}}{{firstName}} {{lastName}}{{/list}}
</script>
<script>
    var context = {
      people: [
        {firstName: "Yehuda", lastName: "Katz"},
        {firstName: "Carl", lastName: "Lerche"},
        {firstName: "Alan", lastName: "Johnson"}
      ]
    };
    Handlebars.registerHelper('list', function(items, options) {
      var out = "<ul>";
    
      for(var i=0, l=items.length; i<l; i++) {
        out = out + "<li>" + options.fn(items[i]) + "</li>";
      }
    
      return out + "</ul>";
    });
    
    
    var source   = $("#entry-template6").html();
    var template = Handlebars.compile(source);
    var html    = template(context);
    document.getElementById("div6").innerHTML = html;
</script>



</body>
</html>
    //handlebars的IF ELSE语句和 each语句的例子:
    <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>test</title>
</head>
<body>

<script src="http://libs.baidu.com/jquery/1.9.0/jquery.js"></script>
<script src="http://cdn.madebyglutard.com/libs/handlebars.js/2.0.0/handlebars.js"></script>

<div id="div7"></div>
<script id="entry-template7" type="text/x-handlebars-template">    
    {{#if haveIf}}我有If{{else}}我没有If{{/if}};
    
    {{#each arr}}
        <p>{{this.a}} &gt; &gt; <span>this.data</span></p> 
    {{/each}}
    
    {{!迭代这条对象}}
    {{#each test}}
            {{!如果满足条件就打印第一个模版， 如果不满足条件就打印第二个模版, helper做的只是对数据进行判断而已}}    
        {{#inverse}}
            <p>{{this.direct}}</p>
        {{else}}
            <p>inverse:{{this.inverse}}</p>
        {{/inverse}}
    {{/each}}
</script>
<script>
    var context = {
        haveIf : true,
        arr : [
            { a : "a" , data : "___a"},
            { a : "b" , data : "___b"},
            { a : "c" , data : "___c"}
        ],
        test : [
            {
                condition : true,
                direct : "打印dir"
            },
            {
                condition : false,
                direct : "dir",
                inverse : "打印inverse"
            }
        ]
    };
    Handlebars.registerHelper('inverse', function(options) {
        if( this.condition ) {
            return options.fn(this);
        }else{
            return options.inverse(this);
        }
    });
    var source   = $("#entry-template7").html();
    var template = Handlebars.compile(source);
    var html    = template(context);
    document.getElementById("div7").innerHTML = html;
</script>
</body>
</html>

    更多handlebars的API查看
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  • 原文地址：https://www.cnblogs.com/diligenceday/p/4105229.html
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