Is there a way to send data using the POST method without a form and without refreshing the page using only pure JavaScript (not jQuery $.post())? Maybe httprequest or something else (just can't find it now)?
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javascript
post
httpwebrequest
xmlhttprequest
http-post
The [new-ish at the time of writing in 2017] Fetch API is intended to make GET requests easy, but it is able to POST as well.
let data = {element: "barium"};
fetch("/post/data/here", {
method: "POST",
body: JSON.stringify(data)
}).then(res => {
console.log("Request complete! response:", res);
});
If you are as lazy as me (or just prefer a shortcut/helper):
window.post = function(url, data) {
return fetch(url, {method: "POST", body: JSON.stringify(data)});
}
// ...
post("post/data/here", {element: "osmium"});
const data = { username: 'example' };
fetch('https://example.com/profile', {
method: 'POST', // or 'PUT'
headers: {
' Content-Type': 'application/json',
},
body: JSON.stringify(data),
})
.then(response => response.json())
.then(data => {
console.log('Success:', data);
})
.catch((error) => {
console.error('Error:', error);
});
Did you know that JavaScript has it's built-in methods and libs to create forms and submit them?
I am seeing a lot of replies here all asking to use a 3rd party library which I think is an overkill.
I would do the following in pure Javascript:
<script>
function launchMyForm()
{
var myForm = document.createElement("FORM");
myForm.setAttribute("id","TestForm");
document.body.appendChild(myForm);
// this will create a new FORM which is mapped to the Java Object of myForm, with an id of TestForm. Equivalent to: <form id="TestForm"></form>
var myInput = document.createElement("INPUT");
myInput.setAttribute("id","MyInput");
myInput.setAttribute("type","text");
myInput.setAttribute("value","Heider");
document.getElementById("TestForm").appendChild(myInput);
// This will create an INPUT equivalent to: <INPUT id="MyInput" type="text" value="Heider" /> and then assign it to be inside the TestForm tags.
}
</script>
This way (A) you don't need to rely on 3rd parties to do the job. (B) It's all built-in to all browsers, (C) faster, (D) it works, feel free to try it out.
I hope this helps. H
Also, RESTful lets you get data back from a POST request.
JS (put in static/hello.html to serve via Python):
<html><head><meta charset="utf-8"/></head><body>
Hello.
<script>
var xhr = new XMLHttpRequest();
xhr.open("POST", "/postman", true);
xhr.setRequestHeader('Content-Type', 'application/json');
xhr.send(JSON.stringify({
value: 'value'
}));
xhr.onload = function() {
console.log("HELLO")
console.log(this.responseText);
var data = JSON.parse(this.responseText);
console.log(data);
}
</script></body></html>
Python server (for testing):
import time, threading, socket, SocketServer, BaseHTTPServer
import os, traceback, sys, json
log_lock = threading.Lock()
log_next_thread_id = 0
# Local log functiondef
def Log(module, msg):
with log_lock:
thread = threading.current_thread().__name__
msg = "%s %s: %s" % (module, thread, msg)
sys.stderr.write(msg + '\n')
def Log_Traceback():
t = traceback.format_exc().strip('\n').split('\n')
if ', in ' in t[-3]:
t[-3] = t[-3].replace(', in','\n***\n*** In') + '(...):'
t[-2] += '\n***'
err = '\n*** '.join(t[-3:]).replace('"','').replace(' File ', '')
err = err.replace(', line',':')
Log("Traceback", '\n'.join(t[:-3]) + '\n\n\n***\n*** ' + err + '\n***\n\n')
os._exit(4)
def Set_Thread_Label(s):
global log_next_thread_id
with log_lock:
threading.current_thread().__name__ = "%d%s" \
% (log_next_thread_id, s)
log_next_thread_id += 1
class Handler(BaseHTTPServer.BaseHTTPRequestHandler):
def do_GET(self):
Set_Thread_Label(self.path + "[get]")
try:
Log("HTTP", "PATH='%s'" % self.path)
with open('static' + self.path) as f:
data = f.read()
Log("Static", "DATA='%s'" % data)
self.send_response(200)
self.send_header("Content-type", "text/html")
self.end_headers()
self.wfile.write(data)
except:
Log_Traceback()
def do_POST(self):
Set_Thread_Label(self.path + "[post]")
try:
length = int(self.headers.getheader('content-length'))
req = self.rfile.read(length)
Log("HTTP", "PATH='%s'" % self.path)
Log("URL", "request data = %s" % req)
req = json.loads(req)
response = {'req': req}
response = json.dumps(response)
Log("URL", "response data = %s" % response)
self.send_response(200)
self.send_header("Content-type", "application/json")
self.send_header("content-length", str(len(response)))
self.end_headers()
self.wfile.write(response)
except:
Log_Traceback()
# Create ONE socket.
addr = ('', 8000)
sock = socket.socket (socket.AF_INET, socket.SOCK_STREAM)
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
sock.bind(addr)
sock.listen(5)
# Launch 100 listener threads.
class Thread(threading.Thread):
def __init__(self, i):
threading.Thread.__init__(self)
self.i = i
self.daemon = True
self.start()
def run(self):
httpd = BaseHTTPServer.HTTPServer(addr, Handler, False)
# Prevent the HTTP server from re-binding every handler.
# https://stackoverflow.com/questions/46210672/
httpd.socket = sock
httpd.server_bind = self.server_close = lambda self: None
httpd.serve_forever()
[Thread(i) for i in range(10)]
time.sleep(9e9)
Console log (chrome):
HELLO
hello.html:14 {"req": {"value": "value"}}
hello.html:16
{req: {…}}
req
:
{value: "value"}
__proto__
:
Object
Console log (firefox):
GET
http://XXXXX:8000/hello.html [HTTP/1.0 200 OK 0ms]
POST
XHR
http://XXXXX:8000/postman [HTTP/1.0 200 OK 0ms]
HELLO hello.html:13:3
{"req": {"value": "value"}} hello.html:14:3
Object { req: Object }
Console log (Edge):
HTML1300: Navigation occurred.
hello.html
HTML1527: DOCTYPE expected. Consider adding a valid HTML5 doctype: "<!DOCTYPE html>".
hello.html (1,1)
Current window: XXXXX/hello.html
HELLO
hello.html (13,3)
{"req": {"value": "value"}}
hello.html (14,3)
[object Object]
hello.html (16,3)
{
[functions]: ,
__proto__: { },
req: {
[functions]: ,
__proto__: { },
value: "value"
}
}
Python log:
HTTP 8/postman[post]: PATH='/postman'
URL 8/postman[post]: request data = {"value":"value"}
URL 8/postman[post]: response data = {"req": {"value": "value"}}
You can send it and insert the data to the body:
var xhr = new XMLHttpRequest();
xhr.open("POST", yourUrl, true);
xhr.setRequestHeader('Content-Type', 'application/json');
xhr.send(JSON.stringify({
value: value
}));
By the way, for get request:
var xhr = new XMLHttpRequest();
// we defined the xhr
xhr.onreadystatechange = function () {
if (this.readyState != 4) return;
if (this.status == 200) {
var data = JSON.parse(this.responseText);
// we get the returned data
}
// end of state change: it can be after some time (async)
};
xhr.open('GET', yourUrl, true);
xhr.send();
If you simply need to POST data and do not require a response from the server, the shortest solution would be to use navigator.sendBeacon():
const data = JSON.stringify({
example_1: 123,
example_2: 'Hello, world!',
});
navigator.sendBeacon('example.php', data);
You can use XMLHttpRequest, fetch API, ...
If you want to use XMLHttpRequest you can do the following
var xhr = new XMLHttpRequest();
xhr.open("POST", url, true);
xhr.setRequestHeader('Content-Type', 'application/json');
xhr.send(JSON.stringify({
name: "Deska",
email: "[email protected]",
phone: "342234553"
}));
xhr.onload = function() {
var data = JSON.parse(this.responseText);
console.log(data);
};
Or if you want to use fetch API
fetch(url, {
method:"POST",
body: JSON.stringify({
name: "Deska",
email: "[email protected]",
phone: "342234553"
})
})
.then(result => {
// do something with the result
console.log("Completed with result:", result);
});
You can use the XMLHttpRequest object as follows:
xhr.open("POST", url, true);
xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded; charset=UTF-8");
xhr.send(someStuff);
That code would post someStuff to url. Just make sure that when you create your XMLHttpRequest object, it will be cross-browser compatible. There are endless examples out there of how to do that.
There is an easy method to wrap your data and send it to server as if you were sending an HTML form using POST.
you can do that using FormData object as following:
data = new FormData()
data.set('Foo',1)
data.set('Bar','boo')
let request = new XMLHttpRequest();
request.open("POST", 'some_url/', true);
request.send(data)
now you can handle the data on the server-side just like the way you deal with reugular HTML Forms.
Additional Info
It is advised that you must not set Content-Type header when sending FormData since the browser will take care of that.
Source: Stackoverflow.com