สมมติเรามี JSON object ที่มีข้อมูลตำแหน่งเมืองของบางประเทศแบบนี้:
const countryInfo = { country: [{ name: "Bangladesh", province: [{ name:"Dhaka", city: [{ name:"Tangail", lat: '11' }, { name:"Jamalpur", lat: '12' }] }, { name: "Khulna", city: [{ name:"Jossore", lat: '22' }, { name:"Tangail", lat: '23' }] }, { name: "Rajshahi", city: [{ name:"Pabna", lat: '33' }, { name:"Rangpur", lat: '33' }] }] },{ name: "India", province: [{ name:"West Bengal", city: [{ name:"Calcutta", lat: '111' }, { name:"Tangail", lat: '112' }] }, { name: "Uttar Pradesh", city: [{ name:"Agra", lat: '122' }, { name:"Tajmahal", lat: '123' }] }, { name: "Rajasthan", city: [{ name:"Kanpur", lat: '131' }, { name:"Jaypur", lat: '132' }] }] }] };เราต้องเขียนฟังก์ชันที่รับออบเจ็กต์แบบนี้และสตริงค้นหา ค้นหาชื่อเมืองทั้งหมดที่ตรงกับสตริงค้นหาและคืนค่าอาร์เรย์ของออบเจ็กต์เมืองที่ตรงกัน
ตัวอย่าง
โค้ดสำหรับนี้:
const countryInfo = { country: [{ name: "Bangladesh", province: [{ name:"Dhaka", city: [{ name:"Tangail", lat: '11' }, { name:"Jamalpur", lat: '12' }] }, { name: "Khulna", city: [{ name:"Jossore", lat: '22' }, { name:"Tangail", lat: '23' }] }, { name: "Rajshahi", city: [{ name:"Pabna", lat: '33' }, { name:"Rangpur", lat: '33' }] }] },{ name: "India", province: [{ name:"West Bengal", city: [{ name:"Calcutta", lat: '111' }, { name:"Tangail", lat: '112' }] }, { name: "Uttar Pradesh", city: [{ name:"Agra", lat: '122' }, { name:"Tajmahal", lat: '123' }] }, { name: "Rajasthan", city: [{ name:"Kanpur", lat: '131' }, { name:"Jaypur", lat: '132' }] }] }] }; const searchForCity = (obj, query) => { const cities = obj.country.reduce((acc, val) => { val.province.forEach(el => { el.city.forEach(elm => { acc.push(elm); }); }); return acc; },[]); const res = cities.filter(el => { return el.name === query; }); return res; }; console.log(searchForCity(countryInfo, 'Tangail'));ผลลัพธ์
ผลลัพธ์ในคอนโซล:
[ { name: 'Tangail', lat: '11' }, { name: 'Tangail', lat: '23' }, { name: 'Tangail', lat: '112' } ]
