The conditional statement in EJS is not functioning properly

I have been incorporating the ejs template into my express application. Following the guidance on the official page of the template (https://www.npmjs.com/package/ejs), I am utilizing an if conditional to display a variable only if it has been defined. Here is an example:

<% if (msg) { %>
  <h2><%=msg %></h2>
<% } else { %>
  <h2>There are no messages</h2>
<% } %>

The issue I am facing is that each time I implement this, the server returns a 500 error. How can I troubleshoot and resolve this problem?

javascriptexpressejs

Answer №1

The error occurs when you try to use if (msg).

To solve this issue, consider checking for existence in a different way, such as using typeof:

<% if (typeof msg != "undefined") { %>
<h2><%=msg %></h2>
<% } else {%>
<h2>No messages available</h2>
<% } %>'

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