How can I comment an HTML tag attribute in HTML source code?

Question

For example:

<a /*title="need to be comment out"*/>a link</a>

Adkisson

Is there a reason you only want to comment them out? Do you need them to exist afterwards? If not you could completely remove them. – Ramsgate

@Ramsgate Just like coding other languages. sometimes, I need to comment it out for testing. – Adkisson

On mac (using the program ; Coda) you can simply press CMD + / after selecting the items ofcourse – Arsenal

A workaround is to have a script (or similar) strip out (remove) such comments before other parts of the system sees it. I did it for WiX source code (pure XML) to able to use comments inside tags. The script was the first to be called by the build process. Per-line comments (//) were also enabled by this. – Repulsion

Related (using <!): Does HTML5 change the standard for HTML commenting? – Repulsion

Answer 1

The W3C documentation suggests it cannot be done:

Note that comments are markup.

This basically means that a <!-- ...> comment tag is just like any other tag, so <a <!--title="need to be comment out"-->>a link</a> is as wrong as <a <span></span>>a link</a>.

For quick hacking I believe a common option is to rename that attribute. While you obtain invalid HTML, you can temporarily remove the attribute:

<a xtitle="need to be comment out">a link</a>

If you happen to be using a server-side language, you can also use its own comment syntax. For instance, in PHP you can do this:

<a <?php/*title="need to be comment out"*/?>>a link</a>

... which generates this HTML:

<a >a link</a>

... and in ASP.NET you can use <%-- Comment goes here --%> while the ASP.NET MVC Razor syntax is @* Comment goes here *@.

Betancourt

You might want to make it more obvious you have purposely "commented" the attribute out. For instance with comment_out_title="...". It may be assumed to be a mispelling. – Gaskin

You do not obtain invalid HTML if you use data- attributes, for example, <a data-xtitle="need to be comment out">a link</a>, though many best practices, including those by such big frameworks as Angular, disadvise this. – Clotilde

A minor thing, but in PHP, you can remove the space, as well, with, for example, <a<? php /* title="need to be comment out"*/ ?>>a link</a>. – Clotilde

Answer 2

You can't. Comments can only start and end outside tags.

Some people preprend an x to an attribute name, thus changing it and causing it to be all but ignored (since it is still often visible in the DOM), but this is invalid.

Dramatization

Yes, this is super-easy, I also do this to "comment" bits of CSS. I call it "spoiling" the line. – Courtesan

Answer 3

I usually just put _x at the end of the attribute name. Then the attribute is ignored because it's unknown. So if I wanted to comment out the id attribute from this element:

<input type="text" name="name" id="name">

I would change it to this:

<input type="text" name="name" id_x="name">

This also has the advantage of being able to search for "_x=" to find all commented attributes.

Saturated

Obviously this trick should only be used when developing and "commented" attributes shouldn't be left in production code. – Saturated

nice, i use just -id="name" – Outpour

@ChrisNash In general, commented out HTML shouldn't be left in code. – Arita

Answer 4

This cannot be done, but an attribute can be removed via the removeAttribute(attribute_name) JavaScript call.

Alternatively, you can prefix the attributes you want removed with a namespace like <a nosuchns:title="nevershown">click</a> and remove the namespace via JavaScript.

Exclusion