表单提交是HTML网页发送HTTP请求的唯一方式吗？

Question

HTML网页提供多少种方式来发送HTTP请求？

https://rawgit.com/markroche92/SDND-Traffic-Sign-Classification/master/structure.JPG structure.JPG 元素中的表单提交是否是HTML网页发送HTTP请求的唯一方式？

Answer 1

您可以使用以下方式。

1. 使用常规表单提交POST和GET

   <a href="something.html">Click here</a>

2. 使用超链接获取

   $.ajax({ url : 'https://reqres.in/api/users?page=2', type : 'GET/POST/PUT/DELETE', data : data, //For POST/PUT/Delete requests success : function(data) { //do response processing here } });

3. 使用AJAX进行POST，PUT，DELETE和GET

       var xhr = new XMLHttpRequest();
       xhr.open('GET', '/server', true);
   
       xhr.onload = function () {
         // Request finished. Do processing here.
       };
   
       xhr.send(null);
       // xhr.send('string');
       // xhr.send(new Blob());
       // xhr.send(new Int8Array());
       // xhr.send({ form: 'data' });
       // xhr.send(document);
   

4. 使用XMLHttpRequest POST，PUT，DELETE和GET

GET ::

    var xhr = new XMLHttpRequest();
    xhr.open("POST/PUT/DELETE", '/server', true);

    //Send the proper header information along with the request
    xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");

    xhr.onreadystatechange = function() {//Call a function when the state changes.
    if(xhr.readyState == XMLHttpRequest.DONE && xhr.status == 200) {
        // Request finished. Do processing here.
    }
    }
    xhr.send("foo=bar&lorem=ipsum"); 
    // xhr.send('string'); 
    // xhr.send(new Blob()); 
    // xhr.send(new Int8Array()); 
    // xhr.send({ form: 'data' }); 
    // xhr.send(document);

POST / PUT / DELETE ::

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = myTableView.dequeueReusableCell(withIdentifier: cellId, for: indexPath) as! ViewControllerTableViewCell
    cell.locationLabel.text = eventsList[indexPath.row].location
    cell.eventTimeLabel.text = eventsList[indexPath.row].dateTime
    cell.eventTypeLabel.text = eventsList[indexPath.row].agencyEventSubtypeCode
    cell.agencyIdLabel.text = eventsList[indexPath.row].agencyId

    if alarmLevel != "0" {
      cell.locationLabel.textColor = UIColor.red
    } else {
      cell.locationLabel.textColor = UIColor.black
    }
    return cell
}