fetch

var form = document.getElementById('searchForm');
var formData = new FormData(form);
if(page != null) {
    formData.append('page', page);
}
fetch('/qna', {
    method: 'POST',
    body: formData
})
.then(response => response.json())
.then(data => {
    list(data);
})
.catch(error => {
});