When I am putting a WordPress value inside the attribute tag, for example, the following method does not need esc_attr
e.g.
// JS code
alert('<?php echo get_bloginfo('name');?>');
the following method does need esc_attr
// JS code
alert('<?php echo esc_attr($post->post_title);?>');
What is the convention used?
You can look at the Codex.
Given that, arguably, both of those strings need sanitization. Imagine a site name like
>> "My" Website's Great Title <<"
Also, since you are using this in Javascript, you should probably be using
esc_js
instead.The convention is, “understand how markup works, and how malicious hackers work, and act accordingly.” That is how you know how to use these functions. Also, Trust No One.
See also this article from our member Stephen Harris: Data Sanitization and Validation With WordPress
You use
esc_attr()
when you are outputting something intended to be in an HTML attribute.In your case, you should be using
esc_js()
, or possiblyjson_encode()
instead.If your post title has single quote in it. Output of your code would be
alert(‘It’s bad’);
that is, breaking your JavaScript code and you will get “Unexpected identifier”. When you use esc_attr, output would be
alert(‘It's bad’);
Post title will be encoded so it works within the strings.