Best practice: escape, or encodeURI / encodeURIComponent

escape()

Don't use it, as it has been deprecated since ECMAScript v3.

encodeURI()

Use encodeURI when you want a working URL. Make this call:

encodeURI("http://www.google.com/a file with spaces.html")

to get:

http://www.google.com/a%20file%20with%20spaces.html

Don't call encodeURIComponent since it would destroy the URL and return

http%3A%2F%2Fwww.google.com%2Fa%20file%20with%20spaces.html

encodeURIComponent()

Use encodeURIComponent when you want to encode a URL parameter.

param = encodeURIComponent('http://xyz.com/?a=12&b=55')
url = 'http://domain.com/?param=' + param ;

And you will get this complete URL:

http://www.domain.com/?param=http%3A%2F%2Fxyz.com%2F%Ffa%3D12%26b%3D55

Note that encodeURIComponent does not escape the ' character.

A common bug is to use it to create html attributes such as href='MyUrl', which could suffer an injection bug.

If you are constructing html from strings, either use " instead of ' for attribute quotes, or add an extra layer of encoding (' can be encoded as %27).

For more information on this type of encoding you can check: http://en.wikipedia.org/wiki/Percent-encoding