jQuery.cookie = function (key, value, options) {

    // key and value given, set cookie...
    if (arguments.length > 1 && (value === null || typeof value !== "object")) {
        options = jQuery.extend({}, options);

        if (value === null) {
            options.expires = -1;
        }

        if (typeof options.expires === ‘number‘) {
            var days = options.expires, t = options.expires = new Date();
            t.setDate(t.getDate() + days);
        }

        return (document.cookie = [
            encodeURIComponent(key), ‘=‘,
            options.raw ? String(value) : encodeURIComponent(String(value)),
            options.expires ? ‘; expires=‘ + options.expires.toUTCString() : ‘‘, // use expires attribute, max-age is not supported by IE
            options.path ? ‘; path=‘ + options.path : ‘‘,
            options.domain ? ‘; domain=‘ + options.domain : ‘‘,
            options.secure ? ‘; secure‘ : ‘‘
        ].join(‘‘));
    }

//存cookie
jQuery.cookie("username","admin",{ expires:7 });
jQuery.cookie("password","123456",{ expires:7 });
//取cookie
var username = $.cookie("username");