How can I use a multiline value for an HTML tag attribute? (i.e. how do I escape newline?)

Question

How do I include a newline in an HTML tag attribute?

For example:

<a href="somepage.html" onclick="javascript: foo('This is a multiline string.
This is the part after the newline.')">some link</a>

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Edit: Sorry, bad example, what if the tag happened to not be in javascript, say:

<sometag someattr="This is a multiline string.
This is the part after the newline." />

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Edit 2: Turns out the newline in the string wasn't my problem, it was the javascript function I was calling. FWIW, "
" can be used for newline in an HTML attribute.

Solution 1

From what I remember about the HTML standard, character entities work in attributes, so this might work:

<sometag someattr="This is a multiline string.&#10;This is the part after the newline." />

I'm not sure if the "newline" you want ought to be 
 (\n) or 
 (\r\n), and I'm not sure if browsers will interpret it the way you want.

Why do you need it? What specific problem are you trying to solve by adding a newline in an HTML tag attribute?

Solution 2

To include a multiline value, just continue the text of the html attribute on the next line in your editor e.g.

<input type="submit" value="hallo
hallo"> 

will put the second hallo under the first

Solution 3

As a general rule newlines in attributes are preserved so your second example would work fine. Did you try it? Can you give a specific example where you are having problems with it?

As test take a look at this:-

<a href="somepage3.html" onclick="javascript: alert(this.getAttribute('thing'))" thing="This is a multiline string.
This is the part after the newline.">some link</a>

The alert include the newline in the attribute.

Solution 4

<a href="somepage.html" onclick="javascript: foo('This is a multiline string. \
This is the part after the newline.')">some link</a>

Javascript needs a backslash at the end of the new line in a string.

View more solutions

Comments

[Kip]

What if it happened to not be within javascript?

[Ricardo Gomes]

are my examples not what you're looking for?

[Kip]

hmm... you're right. the specific problem i was encountering was with the newline inside the javascript, but i assumed it extended to any html attribute in general but i guess i was mistaken. :-/

[Kip]

oops, turns out the problem was actually the javascript function i was calling, not the newline in the tag.

[Thomas L Holaday]

The XML standard for attribute normalization is: w3.org/TR/REC-xml/#AVNormalize You have a good memory :-)

[Bao]

It's not working in my case. Why? <input type="text" name="email" value="Enter email here" title="First line sentence.&#10;Second line sentence.><br />

[Marius Gedminas]

@Baowen: you forgot to terminate your title attribute with a ".

[Bao]

@MariusGedminas Hi thanks, that too. But even after adding the ", it's still not working. I am trying to display those texts in a tooltip via jQuery tooltip function.

[Prasad Silva]

Just to clarify, newlines in attribute values ARE preserved,

[Brian Leishman]

@Bao newline in attributes aren't the same as newlines in the tool tip. A literally newline in HTML doesn't render as a newline

[Wolf]

Great to find this here (and not at first there w3.org/TR/REC-xml/#AVNormalize). This is an important feature for MediaWiki extensions which often pipe arguments through attributes, for example <youtube description"first paragraph&#10;second paragraph">...

[Jcyrss]

What if there are some blank lines in the value? like <iframe srcdoc='....'>. I need put the whole html in the value string, I have to remove all the blank lines of it ?