JavaScript-da AJAX xatolarini to'liq ushlash

fetch tomonidan qaytariladigan promis, faqat tarmoq xatosi yuz berganda xato bilan tugaydi. Agar server 404 yoki 500 holati bilan javob qaytarsa, unda promis muvaffaqiyatli tugaydi, lekin ok holati false ga o'rnatiladi.

Keling, ikkala turdagi xatolarni ushlaymiz:

button.addEventListener('click', function() {
	let promise = fetch('/ajax.html')
	.then(
		response => {
			if (response.ok) {
				return response.text();
			} else {
				console.log('yomon holat javobi');
				return '';
			}
		},
	).then(
		text => {
			console.log(text);
		}
	).catch(
		error => {
			console.log(error);
		}
	);
});

HTTP javobining yomon holati bilan bog'liq xatolik ham catch bloki tomonidan ushlanishi uchun uni throw orqali keyingiga otamiz:

button.addEventListener('click', function() {
	let promise = fetch('/ajax.html')
	.then(
		response => {
			if (response.ok) {
				return response.text();
			} else {
				throw new Error('yomon holat javobi');
			}
		},
	).then(
		text => {
			console.log(text);
		}
	).catch(
		error => {
			console.log(error);
		}
	);
});

Agar so'rov muvaffaqiyatli bo'lsa, sahifa matnini chiqaring, va agar nimadir noto'g'ri ketgan bo'lsa, xatoni chiqaring.