Extensible string utility for converting, identifying and flipping string case

npm install case
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Case: An extensible utility to convert, identify, and flip string case.

Download: Case.min.js or Case.js
Bower: bower install Case (note the big 'C')
NPM: npm install case (little 'c' due to NPM restrictions)


Each of the following functions will first "undo" previous case manipulations before applying the desired case to the given string.

Case.upper('foo_bar')                       -> 'FOO BAR'
Case.lower('fooBar')                        -> 'foo bar'
Case.snake('Foo bar!')                      -> 'foo_bar'
Case.squish('')                      -> 'FooBar'
Case.camel('foo, bar')                      -> 'fooBar'
Case.constant('Foo-Bar')                    -> 'FOO_BAR'
Case.title('foo v. bar')                    -> 'Foo v. Bar''foo_v_bar')                   -> 'Foo V Bar'
Case.sentence('"foo!" said bar', ['Bar'])   -> '"Foo!" said Bar'

sentence(str, names) accepts an array of proper names that should be capitalized, regardless of location in the sentence. This function is specialized, but useful when dealing with input generated with capslock on (i.e. everything my grandma types).

There are three additional functions:

  • of(str): identifies the case of a string, returns undefined if it doesn't match a known type
  • flip(str): reverses the case of letters, no other changes
  • type(name, fn): extends Case with a new case type
Case.of('foo')          -> 'lower'
Case.of('foo_bar')      -> 'snake'
Case.of('Foo v Bar')    -> 'title'
Case.of('foo_ Bar')     -> undefined

Case.flip('FlipMe')     -> 'fLIPmE'
Case.flip('TEST THIS!') -> 'test this!'

Case.type('bang', function(s) {
    return Case.upper(s, '!')+'!';
Case.bang('bang')       -> 'BANG!'
Case.of('TEST!THIS!')   -> 'bang'

Registering functions via type() means Case.of supports them automatically.

Oh, did you notice that little Case.upper(s, '!')? Yeah, upper() and lower() accept a second "fill" argument that will replace any characters which are not letters or numbers. It's handy, sometimes. :)

Release History

  • 2013-06-10 v1.0.0 (public, initial)
  • 2013-08-23 v1.0.3 (fixes for Bower and NPM package definitions, AMD export, strict mode, 'plus' artifact)
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