javascript inside <% %> brackets

Question

I'm using some code I found online but want to understand it better. Works fine but I'm going to need to modify it. What does it mean that much of the js is enclosed in <% %> brackets? Code follows:

        <% AllNetLabs.App_Code.GeoHelper helper1 = new AllNetLabs.App_Code.GeoHelper();
            foreach (var item in helper1.GetSpatialData())
            { %>
                geometries.push('<%=item %>');
        <%  } %>
        <% AllNetLabs.App_Code.GeoHelper helper2 = new AllNetLabs.App_Code.GeoHelper();
            foreach (var item in helper2.GetAttributeData())
            { %>
                attributes.push('<%=item %>');
        <%  } %>

this looks .net and its a razor syntax means gets evaluated on server side — sumeet kumar, Jan 18 '18 at 19:27
That doesn't look like JavaScript inside those brackets at all. Looks more like C#. You might want to double-check where you got this code, as well as what exactly you mean by "works fine". This would most certainly *not* work as JavaScript. — David, Jan 18 '18 at 19:27
And frankly, the code is...not ideal. Using a loop to generate a bunch of `push` statements... — T.J. Crowder, Jan 18 '18 at 19:30
Basically this either isn't JavaScript(likely) and if it IS JavaScript, it's templated by the library/script you're using, so we can't help you without further information. — zfrisch, Jan 18 '18 at 19:34
Also, this is where I found the original reference related to OpenLayers: http://dev.openlayers.org/examples/vector-features-with-text.html — user2084255, Jan 18 '18 at 20:26

score 0 · Answer 1 · answered Jan 18 '18 at 19:29

0

It looks to me that the code in the <% %> blocks is a different language (C#?). Typically, this pattern is used to prepopulate javascript with some values server-side and I would guess that's what's happening here.

answered Jan 18 '18 at 19:29

enkrates

626
1
6
17

score 0 · Answer 2 · answered Jan 18 '18 at 19:30

0

Do you mean EJS? http://www.embeddedjs.com/ Example for the site:

<h1><%= title %></h1>
<ul>
<% for(var i=0; i<supplies.length; i++) {%>
    <li><%= supplies[i] %></li>
<% } %>
</ul>

answered Jan 18 '18 at 19:30

Ribamar Santos

66
5

foreach is not a JavaScript loop. – zfrisch Jan 18 '18 at 19:32

score -1 · Answer 3 · answered Jan 18 '18 at 19:29

-1

They're using dynamic data from the server to push into a JS array.

answered Jan 18 '18 at 19:29

Mustafa Abdul-Kader

13
2

@FranVerona This *is* an answer to the question. If you don't think that it's a sufficiently *useful* answer to the question, you can reflect that opinion by downvoting it, but that doesn't mean it's not an answer. – Servy Jan 18 '18 at 22:07

javascript inside <% %> brackets

3 Answers3