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;
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 <p> 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 <p> Tags</h1> <div class="body"> <p>This is a post about <p> 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 <p> 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)
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:
//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="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>
<!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}} > > <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