How to use underscore.js as a template engine?
I'm trying to learn about new usages of javascript as a serverside language and as a functional language. Few days ago I heard about node.js and express framework. Then I saw about underscore.js as a set of utility functions. I saw this question on stackoverflow . It says we can use underscore.js as a template engine. anybody know good tutorials about how to use underscore.js for templating, especially for biginners who have less experience with advanced javascript. Thanks
Everything you need to know about underscore template is here. Only 3 things to keep in mind:
<% %> - to execute some code <%= %> - to print some value in template <%- %> - to print some values HTML escaped That's all about it.
Simple example:
var tpl = _.template("<h1>Some text: <%= foo %></h1>");
then tpl({foo: "blahblah"}) would be rendered to the string <h1>Some text: blahblah</h1>
<!-- Install jQuery and underscore -->
<script type="text/javascript" src="http://code.jquery.com/jquery-1.7.2.min.js"></script>
<script type="text/javascript" src="http://documentcloud.github.com/underscore/underscore-min.js"></script>
<!-- Create your template -->
<script type="foo/bar" id='usageList'>
<table cellspacing='0' cellpadding='0' border='1' >
<thead>
<tr>
<th>Id</th>
<th>Name</th>
</tr>
</thead>
<tbody>
<%
// repeat items
_.each(items,function(item,key,list){
// create variables
var f = item.name.split("").shift().toLowerCase();
%>
<tr>
<!-- use variables -->
<td><%= key %></td>
<td class="<%= f %>">
<!-- use %- to inject un-sanitized user input (see 'Demo of XSS hack') -->
<h3><%- item.name %></h3>
<p><%- item.interests %></p>
</td>
</tr>
<%
});
%>
</tbody>
</table>
</script>
<!-- Create your target -->
<div id="target"></div>
<!-- Write some code to fetch the data and apply template -->
<script type="text/javascript">
var items = [
{name:"Alexander", interests:"creating large empires"},
{name:"Edward", interests:"ha.ckers.org <nBGSOUND SRC="javascript:alert('XSS');">"},
{name:"..."},
{name:"Yolando", interests:"working out"},
{name:"Zachary", interests:"picking flowers for Angela"}
];
var template = $("#usageList").html();
$("#target").html(_.template(template,{items:items}));
</script>
In it's simplest form you would use it like:
var html = _.template('<li><%= name %></li>', { name: 'John Smith' });
//html is now '<li>John Smith</li>'
If you're going to be using a template a few times you'll want to compile it so it's faster:
var template = _.template('<li><%= name %></li>');
var html = [];
for (var key in names) {
html += template({ name: names[i] });
}
console.log(html.join('')); //Outputs a string of <li> items
I personally prefer the Mustache style syntax. You can adjust the template token markers to use double curly braces:
_.templateSettings.interpolate = /{{(.+?)}}/g;
var template = _.template('<li>{{ name }}</li>');