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Reloading Ajax function with setTimeout doesnt clear previous timeout first

I am trying to load a chat box when a contact name is clicked. On initial load it displays the inbox. All functionality works ok until I try and click the contact name a second time. It loads the new contacts chat but also displays the original contact chat even though I set clearTimeout().
Here is the JS file -
$(document).ready(function(){
var contactTimeout;
var inboxTimeout;
function contact() {
var fromName = $('#from').val();
var toName = $("#to").val();
$(".chat-title").replaceWith("<div class='chat-title'>" + toName + "</div>");
$(".chat-form").fadeIn(100);
$.ajax('chat/get-chat.php', {
data: ({ to: toName,from: fromName}),
type: "POST",
success: function(data) {
$(".chat-body").replaceWith("<div class='chat-body'>" + data + "</div>");
contactTimeout = setTimeout(contact, 2000);
}
});
}
function inbox() {
var user = $('#from').val();
$.ajax('chat/get-chat-inbox.php', {
data: ({ user: user}),
type: "POST",
success: function(data) {
$(".chat-body").replaceWith("<div class='chat-body'>" + data + "</div>");
inboxTimeout = setTimeout(inbox, 2000);
}
});
}
// Load inbox when chat box is opened
$(".chat-arrow").click(function(){
clearTimeout(contactTimeout);
inbox();
});
// Load chat from contact name
$(".contact-name").click(function() {
clearTimeout(contactTimeout); // Here I try and kill previous timeout
clearTimeout(inboxTimeout);
var contactName = $(this).attr('id');
$("#to").val(contactName);
contact();
});
});
Why would it just add more timeout functions rather than replace them when a new contact name is clicked?

First i would suggest you instead of using replace each time, you could easily use .html(data) to put new data in existing content of chat-body.
And explanation is you call your function on ajax success (there's wait time to server respond to your request) and if you click in meanwhile on your another call, you will have two calls instead of one, because you can't clear timer that's not started yet.
Well one of the solutions would be, let timer works only through it's default state, and when you need some fast data, you can call your contact without calling the next timer.
$(document).ready(function(){
var contactTimeout;
var inboxTimeout;
/* add parameter which will mean will we call timer or not */
function contact(dotimer) {
var fromName = $('#from').val();
var toName = $("#to").val();
$(".chat-title").replaceWith("<div class='chat-title'>" + toName + "</div>");
$(".chat-form").fadeIn(100);
$.ajax('chat/get-chat.php', {
data: ({ to: toName,from: fromName}),
type: "POST",
success: function(data) {
$(".chat-body").replaceWith("<div class='chat-body'>" + data + "</div>");
/* default calling of timer with repeating */
if (dotimer) { contactTimeout = setTimeout(function(){ contact(true); }, 2000); }
}
});
}
function inbox() {
var user = $('#from').val();
$.ajax('chat/get-chat-inbox.php', {
data: ({ user: user}),
type: "POST",
success: function(data) {
$(".chat-body").replaceWith("<div class='chat-body'>" + data + "</div>");
inboxTimeout = setTimeout(inbox, 2000);
}
});
}
// Load inbox when chat box is opened
$(".chat-arrow").click(function(){
clearTimeout(contactTimeout);
inbox();
});
// Load chat from contact name
$(".contact-name").click(function() {
clearTimeout(inboxTimeout);
var contactName = $(this).attr('id');
$("#to").val(contactName);
/* call function without TIMER, default one will work as it works */
contact(false);
});
});

Asynchronous AJAX calls (multiple)

I posted this yesterday but i may not have explained my situation well.
I have 3 grids on a page that are built dynamically through JavaScript.
I then have 3 separate JavaScript methods to set a session when a row is clicked in a certain grid.
Once the session is set i would like it to navigate to the next page.
Here is what i have
OnClick event
$('#clinician-planned').on('click', 'tbody>tr>td:not(:last-child):not(:first-child)', function () {
var ID = $(this).closest("tr").children("td.grid__col--id").find("[name=patient-link]").text().trim();
var Location = '#Url.Action("SetPASession", "Clinician")';
AjaxCall(Location, ID);
});
$('#clinician-recent').on('click', 'tbody>tr>td:not(:last-child):not(:first-child)', function () {
var ID = $(this).closest("tr").children("td.grid__col--id").find("[name=patient-link]").text().trim();
var Location = '#Url.Action("SetRDSession", "Clinician")';
AjaxCall(Location, ID);
});
$('#clinician-theatre').on('click', 'tbody>tr>td:not(:last-child):not(:first-child)', function () {
var ID = $(this).closest("tr").children("td.grid__col--id").find("[name=patient-link]").text().trim();
var Location = '#Url.Action("SetTESession", "Clinician")';
AjaxCall(Location, ID);
});
AJAX Post To Controller
function AjaxCall(Location, ID) {
alert('1');
$.ajax({
type: 'POST',
url: Location,
dataType: 'text',
async: false,
contentType: 'application/json; charset=utf-8',
error: function (response) { alert(JSON.stringify(response)); }
}).done(function (response) {
alert('2');
location.href = "#Url.Action("Summary", "Patient")" + "/" + ID;
});
}
Here are the controller methods
public ActionResult SetPASession()
{
Session.Remove("Clinician");
Session["Clinician"] = "pa";
return Json(null);
}
public ActionResult SetRDSession()
{
Session.Remove("Clinician");
Session["Clinician"] = "rd";
return Json(null);
}
public ActionResult SetTESession()
{
Session.Remove("Clinician");
Session["Clinician"] = "te";
return Json(null);
}
The problem i have is when the row is clicked "alert('1'); shows instantly, however it seems like it takes a while and waits for all grids to be populated before the 2nd alert appears. I have tried putting async: false, but this doesnt seem to work.
Any ideas would be much appreciated.

Adding to JSON array by HTML button

I have an AJAX call, as below. This posts data from a form to JSON. I then take the values and put them back into the div called response so as to not refresh the page.
$("form").on("submit", function(event) { $targetElement = $('#response'); event.preventDefault(); // Perform ajax call // console.log("Sending data: " + $(this).serialize()); $.ajax({
url: '/OAH',
data: $('form').serialize(),
datatype: 'json',
type: 'POST',
success: function(response) {
// Success handler
var TableTing = response["table"];
$("#RearPillarNS").empty();
$("#RearPillarNS").append("Rear Pillar Assembly Part No: " + response["RearPillarNS"]);
$("#TableThing").empty();
$("#TableThing").append(TableTing);
for (key in response) {
if (key == 'myList') {
// Add the new elements from 'myList' to the form
$targetElement.empty();
select = $('<select id="mySelect" class="form-control" onchange="myFunction()"></select>');
response[key].forEach(function(item) {
select.append($('<option>').text(item));
});
$targetElement.html(select);
} else {
// Update existing controls to those of the response.
$(':input[name="' + key + '"]').val(response[key]);
}
}
return myFunction()
// End handler
}
// Proceed with normal submission or new ajax call }) });
This generates a new <select id="mySelect">
I need to now extract the value that has been selected by the newly generated select and amend my JSON array. Again, without refreshing the page.
I was thinking of doing this via a button called CreateDrawing
The JS function for this would be:
> $(function() {
$('a#CreateDrawing').bind('click', function() {
$.getJSON('/Printit',
function(data) {
//do nothing
});
return false;
});
});
This is because I will be using the data from the JSON array in a Python function, via Flask that'll be using the value from the select.
My question is, what is the best way (if someone could do a working example too that'd help me A LOT) to get the value from the select as above, and bring into Python Flask/JSON.

Using JavaScript to refresh or retrieve current information on button click

I'll preface this with I'm still new to JavaScript. So problem is in a larger application, our controller is passing in a list of information to the view where certain JavaScript functions rely on certain ViewModel properties. I've written a simple application to hopefully illustrate what I'm getting at.
Below is a sample controller that's passing in List to the Index page:
public ActionResult Index() {
List<int> activeIds = new List<int>();
SqlConnection sqlConn = new SqlConnection(connection_String);
sqlConn.Open();
string sqlStr = "SELECT * FROM dbo.[JS-Test] WHERE Active = 1";
SqlCommand sqlCmd = new SqlCommand(sqlStr, sqlConn);
SqlDataReader sqlDR = sqlCmd.ExecuteReader();
if(sqlDR.HasRows) {
while (sqlDR.Read()) {
activeIds.Add((int)sqlDR["ID"]);
}
}
sqlDR.Close();
sqlCmd.Dispose();
sqlConn.Close();
return View(activeIds);
}
This returns the current "active" items in the database. The (rough) view is as follows...
#model List<int>
#{
ViewBag.Title = "Index";
}
<p>Current Recognized Count: #Model.Count() </p>
Print
<script>
$(document).ready(function () {
$('#printBtn').click(function () {
var numberOfActiveIds = #Model.Count();
$.ajax({
type: "POST",
url: "/Home/PostResults",
data: { ids: numberOfActiveIds},
success: function (results) {
if(results == "Success") {
window.location.href = '/Home/Results';
}
}
});
});
});
</script>
The issue is getting the current number of active items from the database when the button is clicked. Let's say that the user remains idle on the page after it loads for a few minutes. When their page originally loaded, the model returned 5 items listed as active... but while they've been waiting 3 additional items were switched to active in the database for a total of 8. However, when the user finally clicks the button it'll submit 5 items instead of the current 8.
I'm unable to run the query to get the current number of active items in the "/Home/PostResults" ActionResult due to the nature of how the larger application is set up. Is there a way I could refresh the page (getting the updated model) before the rest of the function carries out using values of the refreshed model?
If you have any additional questions, please let me know and I will gladly comply. I've looked at other questions and answers on SO but I haven't found one that quite works for my situation. Thanks!
Edit #1
So, I've added this function to the Home controller which just returns the list count as Json.
public ActionResult GetIds(){
List<int> activeIds = new List<int>();
SqlConnection sqlConn = new SqlConnection(connection_String);
sqlConn.Open();
string sqlStr = "SELECT * FROM dbo.[JS-Test] WHERE Active = 1";
SqlCommand sqlCmd = new SqlCommand(sqlStr, sqlConn);
SqlDataReader sqlDR = sqlCmd.ExecuteReader();
if (sqlDR.HasRows) {
while (sqlDR.Read()) {
activeIds.Add((int)sqlDR["ID"]);
}
}
sqlDR.Close();
sqlCmd.Dispose();
sqlConn.Close();
return Json(activeIds.Count());
}
The view script now looks like this...
<script>
$(document).ready(function () {
$('#printBtn').click(function () {
var numberOfActiveIds = #Model.Count();
$.ajax({
type: "GET",
url: "/Home/GetIds",
success: function(response) {
numberOfActiveIds = response;
$.ajax({
type: "POST",
url: "/Home/PostResults",
data: { ids: numberOfActiveIds},
success: function (results) {
if(results == "Success") {
window.location.href = '/Home/Results';
}
}
});
}
});
});
});
</script>
I'm currently getting the following error...
Failed to load resource: the server responded with a status of 500 (Internal Server Error)
Edit #2
I had to set the JsonRequestBehavior to AllowGet for it to work properly. Thanks again, everyone!

gforce301 mentioned to GET the current actives via an ajax call to an additional, separate method making the query to the database and THEN ajax post the returned "actives". Is that possible?
Yes this is possible. That's why I mentioned it. Irregardless of other peoples opinions on how they think you should do this, I understand that you may be limited on why you can't do it their way even if they don't.
The code below is a restructuring of your code. It chains 2 ajax calls together, with the second one depending on the success of the first. Notice the comment block in the success handler of the first ajax call. Since I don't know what the response will be, I can't fill in the part on how to use it. This accomplishes your goal of having the user only make a single button click.
<script>
$(document).ready(function () {
$('#printBtn').click(function () {
var numberOfActiveIds = #Model.Count();
$.ajax({
type: 'GET',
url: '/path/to/get/activeIds',
success: function(response) {
/*
Since I don't know the structure of response
I have to just explain.
use response to populate numberOfActiveIds
now we just make our post ajax request.
*/
$.ajax({
type: "POST",
url: "/Home/PostResults",
data: { ids: numberOfActiveIds},
success: function (results) {
if(results == "Success") {
window.location.href = '/Home/Results';
}
}
});
}
});
});
});
</script>

I can give you an idea, i hope it can help,
run another ajax 1st on btnclick to get the data(or datat count) again, if the record count is greater then current then update the view and don't PostResults and if its same then just PostResults
on ajax success you can reload the data or view
and on failure(when no new record) just do PostResults

Append the last message once

Hello guys i am trying to build a chat with Jquery , php , ajax and mysql
the problem that i am facing since few days is that when i get the value of the last message its keep getting append to the div what i want is to append the last message only once , and append again if there is a new message here is my ajax call
var chat = "";
$.ajax({
url: "php/gt_user.php",
type: "get",
success: function (result) {
var gtUser = $.parseJSON(result);
$.each(gtUser, function (idx, obj) {
var usrApp = "<span><i class='fa fa-user-circle-o' aria-hidden='true'></i>";
usrApp += "<p class='usr-name'>" + obj.Tables_in_chat + "</p></span>";
$('.userarea').append(usrApp);
}); // here i get all the username who sent a message and print them on a div
$('.userarea span').on('click', function () {
$('.msgarea').html("");
var usrName = $(this).text();
$('#usrname').text(usrName);
setInterval(function () {
$.ajax({
url: "php/admin_msg.php",
type: "post",
data: {
name: usrName
},
success: function (result) {
var lastmsg = result;
function appedn() {
var usrMsg = "<div class='usr-msg'><i class='fa fa-user-circle-o' aria-hidden='true'></i>";
usrMsg += "<span><p>" + lastmsg + "</p></span></div>";
$('.msgarea').append(usrMsg);
}
if (chat !== result) {
appedn();
} else {
chat = result;
}
}
});
}, 2000);
});
}
});
the respanse from php/admin_msg.php is working and i got the last message sucessfully the problem is that this script keep adding the same message to the message area , and what i want is to added the message only once if there is a new one

You need to somehow identify last message that is already appended to your html the best would be some id sent from server. So your message div should containt some data-id attribute, and then when you ask for next message get last children of $('.msgarea') element, read it data-id and compare with current one.
Another thing I would recommend to moving to some view library or framework, react, angular, vue or whatever. It gets complicated when you want to manage such features with pure jQuery.

i was finally able to fix the problem after 1 day of struggle so will post the answear here just in case it will help some one else facing the same issue
the part where i had to get all the username table from database i move it to my HTML and used a few line of php to echo the result like this(each user name has his own table)
// show all the user name that sent a message
$result = $con->query("show tables from chat");
while($row = mysqli_fetch_assoc($result)){
echo "<span><i class='fa fa-user-circle-o' aria-hidden='true'></i><p class='usr-name'>".$row['Tables_in_chat']."</p></span>";
}
then on my jquery script i moved the function that check for the last message every 2sec outside the click event so my Jquery script look more cleaner now
/* get the user name and added it to the header of the message box */
$('.userarea span').on('click', function () {
$('.msgarea').html("");
var usrName = $(this).text();
$('#usrname').text(usrName);
});
var chatdata = "";
/* check for new message and append the message area if there is a new one */
setInterval(function () {
var usrName = $('#usrname').text();
$.ajax({
url: "php/admin_msg.php",
type: "post",
data: {
name: usrName
},
success: function (result) {
function appedn() {
var usrMsg = "<div class='usr-msg'><i class='fa fa-user-circle-o' aria-hidden='true'></i>";
usrMsg += "<span><p>" + result + "</p></span></div>";
$('.msgarea').append(usrMsg);
}
if (chatdata !== result) {
appedn();
chatdata = result;
}
}
});
}, 2000);