1、各种模板引擎性能对比
移动端稍微复杂点的页面肯定是需要用模板的，模板越小越好，当然也得兼顾性能，目前doT.js是一个不错的选择。
各模板性能对比
doT地址
该模板各方面性能都很优秀，缺点在于不好调试，不过只要保证语法正确，一般不会出错
2、语法
- 插值
{{=it.xxx }} - 取值
{{=xxx }}
插值和取值差不多，取值一般用于for循环中，取值不用加it - JS运算
{{...}} 可以放js表达式，如for循环 - 遍历数组
{{~it.array :value:index}} ...{{~}} - 遍历对象
{{ for var key in data { }}
{{= key }}
{{ } }} - 三木运算
{{=(it.value=='somevalue'?'value1':'value2')}}
常用于动态添加某个类名 - 条件判断
{{? }} 表if
{{??}}表else if
{{??}}表else
example:
//template
{{? it.name }}
<div>Oh, I love your name, {{=it.name}}!</div>
{{?? it.age === 0}}
<div>Guess nobody named you yet!</div>
{{??}}
You are {{=it.age}} and still don't have a name?
{{?}}
//data
{"name":"Jake","age":31}
- encoding后再插值
{{!it.xxx}} - 编译时取值
{{# }} for compile-time evaluation/includes and partials - 编译时定义
{{## #}} for compile-time defines
3、使用注意
- 双括号中的前缀，如'?',"~","#"等要紧挨左边的双括号，不能有空格，这些前缀后面的表达式与前缀之间有没有空格无所谓；
- 条件判断和数组遍历语法要有对应的结束符，如{{?it.xxx}}{{?}},
{{~it.array :value:index}}{{~}}
4、使用方式
- 引入dot.js;
- render=doT.template(tpl),这一步返回一个函数;
- domString=render(data),这一步返回dom的string形式;
- xxx.innerHTML=domString;
5、实例
//实例1：简单语法
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Test doT.js</title>
</head>
<body>
<div id="content"></div>
<template id="tmpl">
{{ for(var prop in it) { }}
<div>{{=prop}}</div>
{{ } }}
</template>
<script src='doT.js'></script>
<script>
var data={"name":"Jake","age":31,"mother":"Kate","father":"John","interests":["basketball","hockey","photography"],"contact":{"email":"jake@xyz.com","phone":"999999999"}};
var tmpl=document.getElementById('tmpl');
var rendered=doT.template(tmpl.innerHTML)(data);
var content=document.getElementById('content');
content.innerHTML=rendered;
</script>
</body>
</html>
//实例2：编译时定义与取值
<html>
<head>
<script id="headertmpl" type="text/x-dot-template">
<h1>{{=it.title}}</h1>
</script>
<script id="pagetmpl" type="text/x-dot-template">
<h2>Here is the page using a header template</h2>
{{#def.header}}
{{=it.name}}
</script>
<script id="customizableheadertmpl" type="text/x-dot-template">
{{#def.header}}
{{#def.mycustominjectionintoheader || ''}}
</script>
<script id="pagetmplwithcustomizableheader" type="text/x-dot-template">
<h2>Here is the page with customized header template</h2>
{{##def.mycustominjectionintoheader:
<div>{{=it.title}} is not {{=it.name}}</div>
#}}
{{#def.customheader}}
{{=it.name}}
</script>
<script src="./doT.js" type="text/javascript"></script>
</head>
<body>
<div id="content"></div>
<div id="contentcustom"></div>
</body>
<script type="text/javascript">
var def = {
header: document.getElementById('headertmpl').text,
customheader: document.getElementById('customizableheadertmpl').text
};
var data = {
title: "My title",
name: "My name"
};
var pagefn = doT.template(document.getElementById('pagetmpl').text, undefined, def);
document.getElementById('content').innerHTML = pagefn(data);
pagefn = doT.template(document.getElementById('pagetmplwithcustomizableheader').text, undefined, def);
document.getElementById('contentcustom').innerHTML = pagefn(data);
</script>
</html>
6、使用注意
- 在使用条件判断时{{?it.value>=number}},其中的大于号会被转义，因此需要自己进行反转义：
function htmlDecode(str) {
var s = "";
if (str.length == 0) return "";
s = str.replace(/&/g, "&");
s = s.replace(/</g, "<");
s = s.replace(/>/g, ">");
s = s.replace(/ /g, " ");
s = s.replace(/'/g, "\'");
s = s.replace(/"/g, "\"");
// s = s.replace(/<br>/g, "\n");
return s;
}
