string.toLocaleLowerCase()

這個需要和string.toLowerCase()分辨一下,

string.toLocaleLowerCase():

--> converts a string to lowercase letters, according to the host's current locale.

-->The locale is based on the language settings of the browser.

JavaScript String toLocaleLowerCase() Method:
http://www.w3schools.com/jsref/jsref_tolocalelowercase.asp