JavaScript
Wat is de Fetch API en hoe maak je HTTP requests?
Fetch API maakt HTTP requests vanuit JavaScript naar servers.
Fetch syntax
fetch(url, { method: 'GET', headers: {...}, body: JSON.stringify(...) }) Returns Promise Response moet parsed worden (json(), text(), blob())
REST methods
GET - ophalen van data POST - nieuwe data toevoegen PUT/PATCH - bestaande data updaten DELETE - verwijderen
Code Voorbeelden
JAVASCRIPTFetch GET en POST
// GET request
async function fetchUsers() {
try {
const response = await fetch('https://api.example.com/users');
const data = await response.json();
console.log(data);
} catch (err) {
console.error('Error:', err);
}
}
// POST request
async function createUser(userData) {
const response = await fetch('https://api.example.com/users', {
method: 'POST',
headers: {
'Content-Type': 'application/json',
},
body: JSON.stringify(userData)
});
const newUser = await response.json();
console.log('Created:', newUser);
}
// PUT request (update)
async function updateUser(id, userData) {
const response = await fetch(`https://api.example.com/users/${id}`, {
method: 'PUT',
headers: { 'Content-Type': 'application/json' },
body: JSON.stringify(userData)
});
return response.json();
}
// DELETE request
async function deleteUser(id) {
await fetch(`https://api.example.com/users/${id}`, {
method: 'DELETE'
});
}💡 Praktijk Tips
Altijd try/catch gebruiken. Controleer response.ok voordat je response.json() aanroept.
Relevante trefwoorden
fetchAPIasyncHTTP