chore: add uppercaseNum

Author: Simon he

src/uppercaseNum.ts

@@ -0,0 +1,30 @@
+export function uppercaseNum(n: number) {
+  const fraction = ['角', '分'];
+  const digit = [
+    '零', '壹', '贰', '叁', '肆',
+    '伍', '陆', '柒', '捌', '玖'
+  ];
+  const unit = [
+    ['元', '万', '亿'],
+    ['', '拾', '佰', '仟']
+  ];
+  const head = n < 0 ? '欠' : '';
+  n = Math.abs(n);
+  let s = '';
+  for (let i = 0; i < fraction.length; i++) {
+    s += (digit[Math.floor(n * 10 * Math.pow(10, i)) % 10] + fraction[i]).replace(/零./, '');
+  }
+  s = s || '整';
+  n = Math.floor(n);
+  for (let i = 0; i < unit[0].length && n > 0; i++) {
+    let p = '';
+    for (let j = 0; j < unit[1].length && n > 0; j++) {
+      p = digit[n % 10] + unit[1][j] + p;
+      n = Math.floor(n / 10);
+    }
+    s = p.replace(/(零.)*零$/, '').replace(/^$/, '零') + unit[0][i] + s;
+  }
+  return head + s.replace(/(零.)*零元/, '元')
+    .replace(/(零.)+/g, '零')
+    .replace(/^整$/, '零元整');
+}