Fetch API

fetch("https://api.example.com/users")
  .then((response) => response.json())
  .then((users) => console.log(users))
  .catch((error) => console.error(error));

async function loadUsers() {
  try {
    const response = await fetch(
      "https://api.example.com/users"
    );

    if (!response.ok) {
      throw new Error("নেটওয়ার্ক ভুল");
    }

    const users = await response.json();
    console.log(users);
  } catch (error) {
    console.error("ডেটা আনা ব্যর্থ:", error);
  }
}

loadUsers();

const newUser = {
  name: "রহিম",
  email: "rahim@example.com",
};

fetch("https://api.example.com/users", {
  method: "POST",
  headers: {
    "Content-Type": "application/json",
  },
  body: JSON.stringify(newUser),
})
  .then((response) => response.json())
  .then((data) => console.log("তৈরি হয়েছে:", data));

async function updateUser(id, updated) {
  const res = await fetch(`https://api.example.com/users/${id}`, {
    method: "PUT",
    headers: {
      "Content-Type": "application/json",
    },
    body: JSON.stringify(updated),
  });

  if (!res.ok) throw new Error(`HTTP ${res.status}`);
  return res.json();
}

// পুরো object-টি প্রতিস্থাপন
await updateUser(1, { name: "করিম", email: "karim@example.com" });

async function patchUser(id, updates) {
  const res = await fetch(`https://api.example.com/users/${id}`, {
    method: "PATCH",
    headers: {
      "Content-Type": "application/json",
    },
    body: JSON.stringify(updates),
  });

  if (!res.ok) throw new Error(`HTTP ${res.status}`);
  return res.json();
}

// শুধু ভাঙা field
await patchUser(1, { email: "new@example.com" });

async function deleteUser(id) {
  const res = await fetch(`https://api.example.com/users/${id}`, {
    method: "DELETE",
  });

  if (!res.ok && res.status !== 204) {
    throw new Error(`HTTP ${res.status}`);
  }
  console.log("মুছে ফেলা হয়েছে");
}

await deleteUser(1);

const headers = new Headers();
headers.set("Content-Type", "application/json");
headers.set("Authorization", "Bearer " + token);

const res = await fetch("/api/private", {
  method: "GET",
  headers,
});

// উত্তরের headers পড়া
console.log(res.headers.get("content-type"));

async function request(url, options = {}) {
  try {
    const res = await fetch(url, options);
    if (!res.ok) {
      throw new Error(`HTTP ${res.status} ${res.statusText}`);
    }

    const contentType = res.headers.get("content-type") || "";
    return contentType.includes("application/json")
      ? await res.json()
      : await res.text();
  } catch (err) {
    // network error / non-2xx
    throw new Error("রিকোয়েস্ট ব্যর্থ: " + err.message);
  }
}

// ব্যবহার
const users = await request("/api/users");
await request("/api/users/1", { method: "DELETE" });

<button id="load">ডেটা লোড</button>
<ul id="list"></ul>

<script>
  document.getElementById("load")
    .addEventListener("click", async () => {
      const res = await fetch("/api/users");
      const users = await res.json();
      const list = document.getElementById("list");

      list.innerHTML = users
        .map(u => "<li>" + u.name + "</li>")
        .join("");
    });
</script>