将数字转为汉字写法（不可以超过）
function toZhDigit(digit) {
digit = typeof digit === "number" ? String(digit) : digit;
const zh = ["零", "一", "二", "三", "四", "五", "六", "七", "八", "九"];
const unit = ["千", "百", "十", ""];
const quot = ["万","亿","兆","京","垓","秭","穰","沟","涧","正","载","极","恒河沙","阿僧祗","那由他","不可思议","无量","大数"];
let breakLen = Math.ceil(digit.length / 4);
let notBreakSegment = digit.length % 4 || 4;
let segment;
let zeroFlag = [],
allZeroFlag = [];
let result = "";
while (breakLen > 0) {
if (!result) {
// 第一次执行
segment = digit.slice(0, notBreakSegment);
let segmentLen = segment.length;
for (let i = 0; i < segmentLen; i++) {
if (segment[i] != 0) {
if (zeroFlag.length > 0) {
result += "零" + zh[segment[i]] + unit[4 - segmentLen + i];
// 判断是否需要加上 quot 单位
if (i === segmentLen - 1 && breakLen > 1) {
result += quot[breakLen - 2];
}
zeroFlag.length = 0;
} else {
result += zh[segment[i]] + unit[4 - segmentLen + i];
if (i === segmentLen - 1 && breakLen > 1) {
result += quot[breakLen - 2];
}
}
} else {
// 处理为 0 的情形
if (segmentLen == 1) {
result += zh[segment[i]];
break;
}
zeroFlag.push(segment[i]);
continue;
}
}
} else {
segment = digit.slice(notBreakSegment, notBreakSegment + 4);
notBreakSegment += 4;
for (let j = 0; j < segment.length; j++) {
if (segment[j] != 0) {
if (zeroFlag.length > 0) {
// 第一次执行zeroFlag长度不为0，说明上一个分区最后有0待处理
if (j === 0) {
result += quot[breakLen - 1] + zh[segment[j]] + unit[j];
} else {
result += "零" + zh[segment[j]] + unit[j];
}
zeroFlag.length = 0;
} else {
result += zh[segment[j]] + unit[j];
}
// 判断是否需要加上 quot 单位
if (j === segment.length - 1 && breakLen > 1) {
result += quot[breakLen - 2];
}
} else {
// 第一次执行如果zeroFlag长度不为0, 且上一划分不全为0
if (j === 0 && zeroFlag.length > 0 && allZeroFlag.length === 0) {
result += quot[breakLen - 1];
zeroFlag.length = 0;
zeroFlag.push(segment[j]);
} else if (allZeroFlag.length > 0) {
// 执行到最后
if (breakLen == 1) {
result += "";
} else {
zeroFlag.length = 0;
}
} else {
zeroFlag.push(segment[j]);
}
if (
j === segment.length - 1 &&
zeroFlag.length === 4 &&
breakLen !== 1
) {
// 如果执行到末尾
if (breakLen === 1) {
allZeroFlag.length = 0;
zeroFlag.length = 0;
result += quot[breakLen - 1];
} else {
allZeroFlag.push(segment[j]);
}
}
continue;
}
}
--breakLen;
}
return result;
}
}
