js 将数值金额转换成大写金额

/**
 * @description 将数值金额转换成大写金额
 * @date 2019-01-29
 * @export
 * @param {*} n 数值金额
 * @returns string
 */
export function digitUppercase(n) {
    const fraction = ['角', '分'];
    const digit = ['零', '壹', '贰', '叁', '肆', '伍', '陆', '柒', '捌', '玖'];
    const unit = [['元', '万', '亿'], ['', '拾', '佰', '仟']];
    let num = Math.abs(n);
    let s = '';
    fraction.forEach((item, index) => {
        s += (digit[Math.floor(num * 10 * 10 ** index) % 10] + item).replace(/零./, '');
    });
    s = s || '整';
    num = Math.floor(num);
    for (let i = 0; i < unit[0].length && num > 0; i += 1) {
        let p = '';
        for (let j = 0; j < unit[1].length && num > 0; j += 1) {
            p = digit[num % 10] + unit[1][j] + p;
            num = Math.floor(num / 10);
        }
        s = p.replace(/(零.)*零$/, '').replace(/^$/, '零') + unit[0][i] + s;
    }
    return s
        .replace(/(零.)*零元/, '元')
        .replace(/(零.)+/g, '零')
        .replace(/^整$/, '零元整');
}