jquery - Escape square brackets when assigning a class name to an element

Question

Does anyone know how to escape the square bracket character when setting a class name with jQuery?

Try the following:

$('#txtFirstname').addClass('test[someval]')

then

$('#txtFirstname').attr('class')

you'll see the class is there.

Now try

$('#txtFirstname').hasClass('test[someval]')

FAIL

The only reason I can think of is the square brackets.

And I need these for my jQuery validation you see.

Answer 1

Escape with TWO (2) backslashes.

http://learn.jquery.com/using-jquery-core/faq/how-do-i-select-an-element-by-an-id-that-has-characters-used-in-css-notation/