fetch('http://your-api-endpoint.com/api/some-endpoint', {
    method: 'GET',
    headers: {
        'Origin': 'http://example.com',
        'Content-Type': 'application/json'
    }
})
.then(response => response.json())
.then(data => console.log(data))
.catch(error => console.error('Error:', error));

如果接口允许跨域，响应会正常返回。 如果接口不允许跨域，控制台会显示类似以下的错误：

Access to fetch at 'http://your-api-endpoint.com/api/some-endpoint' from origin 'http://example.com' has been blocked by CORS policy.