AJAX傳輸
例:const xhr = new XMLHttpRequest();
// 此方法因為狀態改變被調用多次,實測執行三次(1->2->4)
xhr.onreadystatechange = () => {
if (xhr.readystate === 4 && xhr.status === 200) {
console.log(‘upload success’);
} else {
console.log(‘upload fail);
}
};
xhr.open(‘PUT’, ’網址’);
xhr.setRequestHeader(‘content-type’, ‘application/octet-stream’);
xhr.send(圖片文件file);