Question

I’ve been comparing different JavaScript template engines to see which one gives me the best performance for large sets of data. One that I ran across is Underscore.js. However, I haven’t been able to get any of the examples working. My template looks like:

<% _.each(projects(), function(project) { %>
   <tr>
      <td><%= project.code %></td>
      <td><%= project.request %></td>
      <td><%= project.stage %></td>
      <td><%= project.type %></td>
      <td><%= project.launch %></td>
   </tr>
<% }) %>

However, when I run the page I get a server-side ASP.NET exception, as it’s trying to compile the text within the <% ... %> tags:

Compiler Error Message: CS1026: ) expected
Line 826:                     <% _.each(projects(), function(project) { %>

I was unable to find a way to escape these tags, nor was I able to find a way to configure Underscore to use a different syntax. Is there a workaround, or are Underscore and ASP.NET simply incompatible with each other?

Answer 1

Same issue with JSP, so we do this:

_.templateSettings = {interpolate : /\{\{(.+?)\}\}/g,      // print value: {{ value_name }}
                      evaluate    : /\{%([\s\S]+?)%\}/g,   // excute code: {% code_to_execute %}
                      escape      : /\{%-([\s\S]+?)%\}/g}; // excape HTML: {%- <script> %} prints &lt;script&gt;

This will allow you to use all the various versions of the tag outputs: interpolation, evaluation and escaping.