function string10to64(number) {

    var chars = '0123456789abcdefghigklmnopqrstuvwxyzABCDEFGHIGKLMNOPQRSTUVWXYZ-~'.split(''),

        radix = chars.length,

        qutient = +number,

        arr = [];

    do {

        mod = qutient % radix;

        qutient = (qutient - mod) / radix;

        arr.unshift(chars[mod]);

    } while (qutient);

    return arr.join('');

}

function string64to10(number_code) {

    var chars = '0123456789abcdefghigklmnopqrstuvwxyzABCDEFGHIGKLMNOPQRSTUVWXYZ-~',

        radix = chars.length,

        number_code = String(number_code),

        len = number_code.length,

        i = 0,

        origin_number = 0;

    while (i < len) {

        origin_number += Math.pow(radix, i++) * chars.indexOf(number_code.charAt(len - i) || 0);

    }

    return origin_number;

}