การแปลงตัวเลขเงินบาทเป็นตัวอักษรภาษาอังกฤษรองรับสตางค์ใน JavaScript

บทความนี้สาธิตฟังก์ชันแปลงตัวเลขทศนิยม (สูงสุด 2 ตำแหน่ง) เป็นคำอ่านภาษาอังกฤษแบบสกุลเงินอินเดีย (ใช้หน่วย Thousand, Lakh, Crore)

ตัวอย่าง

const num = 12500;
// ผลลัพธ์: 'Twelve Thousand Five Hundred'

ตัวอย่างโค้ด

const num = 12500;

const wordify = (num) => {
  const single = ["Zero", "One", "Two", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine"];
  const double = ["Ten", "Eleven", "Twelve", "Thirteen", "Fourteen", "Fifteen", "Sixteen", "Seventeen", "Eighteen", "Nineteen"];
  const tens = ["", "Ten", "Twenty", "Thirty", "Forty", "Fifty", "Sixty", "Seventy", "Eighty", "Ninety"];

  const formatTenth = (digit, prev) => {
    return 0 == digit ? "" : " " + (1 == digit ? double[prev] : tens[digit]);
  };

  const formatOther = (digit, next, denom) => {
    return (0 != digit && 1 != next ? " " + single[digit] : "") + (0 != next || digit > 0 ? " " + denom : "");
  };

  let res = "";
  let index = 0;
  let digit = 0;
  let next = 0;
  let words = [];

  if (num += "", isNaN(parseInt(num))) {
    res = "";
  } else if (parseInt(num) > 0 && num.length <= 10) {
    for (index = num.length - 1; index >= 0; index--) {
      switch (digit = num[index] - 0, next = index > 0 ? num[index - 1] - 0 : 0, num.length - index - 1) {
        case 0: words.push(formatOther(digit, next, "")); break;
        case 1: words.push(formatTenth(digit, num[index + 1])); break;
        case 2: words.push(0 != digit ? " " + single[digit] + " Hundred" + (0 != num[index + 1] && 0 != num[index + 2] ? " and" : "") : ""); break;
        case 3: words.push(formatOther(digit, next, "Thousand")); break;
        case 4: words.push(formatTenth(digit, num[index + 1])); break;
        case 5: words.push(formatOther(digit, next, "Lakh")); break;
        case 6: words.push(formatTenth(digit, num[index + 1])); break;
        case 7: words.push(formatOther(digit, next, "Crore")); break;
        case 8: words.push(formatTenth(digit, num[index + 1])); break;
        case 9: words.push(0 != digit ? " " + single[digit] + " Hundred" + (0 != num[index + 1] || 0 != num[index + 2] ? " and" : " Crore") : "");
      }
    }
    res = words.reverse().join("");
  } else res = "";
  return res;
};

console.log(wordify(num));

ผลลัพธ์

Twelve Thousand Five Hundred

คำอธิบาย

อัลกอริทึมประมวลผลตัวเลขจากหลักหน่วยขึ้นไป ใช้ switch case ตามตำแหน่งหลัก (ones, tens, hundreds, thousands, lakhs, crores)

รองรับระบบนับอินเดีย: 1 Lakh = 100,000, 1 Crore = 10,000,000

โค้ดซับซ้อน สำหรับการใช้งานจริงแนะนำใช้ library เช่น numbro หรือ numeral พร้อม locale