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jQuery: How to get input value within an ajax call?

I have a jQuery script, in which I need to load data from a CSV from an external URL.
At the same time, I need to combine the data from the CSV with data provided by a frontend user through an input field. My expected result would be that I'd be able to call the jQuery code for fetching the value from the user's entry into the input field. However, while this works when the code is placed outside the ajax call, it does not work inside.
At the same time, I can't place the code for fetching the user's input outside the ajax call, as I need to be able to utilize information from the loaded CSV together with the user input to perform a dynamic calculation.
My code is as below:
HTML:
<input type="text" id="my_input" value="12" maxlength="2">
Javascript:
$.ajax({
url: csv_url,
async: false,
success: function (csvd) {
var csv = $.csv.toObjects(csvd);
// XYZ done with the CSV data to populate various fields
$("#my_input").keyup(function () {
console.log(this.value);
// this does not result in anything being logged
});
},
dataType: "text",
complete: function () {}
});

Of course it will not work. You are telling the compiler to add the keyup event listener to input after the ajax call is successful. Which means it will not work until ajax call is completed successfully.
You need to put the keyup event listener outside and inside the ajax call just get the value like below:
let myInputValue = "";
$("#my_input").keyup(function () {
console.log(this.value);
myInputValue = this.value;
});
$.ajax({
url: csv_url,
async: false,
success: function (csvd) {
var csv = $.csv.toObjects(csvd);
// XYZ done with the CSV data to populate various fields
//And later use the myInputValue here
},
dataType: "text",
complete: function () {}
});
You have not give us enough info. if you only need the current value in the ajax call you can do like below:
$.ajax({
url: csv_url,
async: false,
success: function (csvd) {
var csv = $.csv.toObjects(csvd);
// XYZ done with the CSV data to populate various fields
let myInputValue = $("#my_input").val();//And later use the myInputValue here
},
dataType: "text",
complete: function () {}
});

passing data from laravel view to controller via ajax onchange event

I have a dropdown list in a blade view. I want to send the value of the selected item to the controller immediately onchange. I have 2 routes in web.php:
Route::get('/plots', 'PlotController#index');
Route::get('/plots/{testId}', 'PlotController#getData');
The first one populates the dropdown list. The second one is supposed send the value of the dropdown list to the controller, which pulls stuff from mysql and sends the data back to the view, which draws a chart. I can get the dropdown to populate ok, but I can't figure out how to send the selected value to the controller. I'm trying to use ajax to do it like this:
$(document).ready(function() {
$('#sel_test').change(function() {
var testId = $(this).val();
console.log("testId=" + testId);
$.ajax({
url: 'plots/' + testId,
type: 'get',
dataType: 'json',
success: function(response) {
console.log("success");
}
});
});
});
The testId output to the console is correct but it never makes it to the controller. The error I see in the console is:
GET http://homestead.test/plots/1 500 (Internal Server Error)
I'm pretty new to laravel and find it extremely confusing. Can anyone explain the correct way to do this?
EDIT:
After testing and confirming Rian's answer as correct, I then tried to implement the real code, which of course is much more complicated. Instead of the controller returning the input test_id:
return $request->test_id;
It actually returns a more complex structure:
return view('plot')
->with('measurements',json_encode($result))
->with('events',json_encode($timeline))
->with('limits',json_encode($limits));
When I uncomment the original controller code, including the return section above, it seems to affect the ability of the controller to return anything at all. Here is the first few lines of the PlotController getData method:
public function getData(Request $request) {
Log::debug("made it to PlotController.php#getData");
Log::debug("test_id="+$request->testId);
And here is the log output:
[2020-02-23 16:43:52] laravel.DEBUG: made it to
PlotController.php#getData
The second line does not output anything. Here is what I see in the javascript console after I select an item from the dropdown list:
testId=49 jquery.min.js:2 GET
http://homestead.test/get-data-by-id?test_id=49 500 (Internal Server
Error)
Any ideas?

The easiest way is to get the data in Laravel Request. At least that's how I do it.
So your route shouldn't contain any parameter for that.
Your route will look like this:
Route::get('get-data-by-id', 'PlotController#getData')->name('get.data.by.id');
Your ajax should be like this:
$(document).on('change', '#sel_test',function(){
var testId = $(this).val();
$.ajax({
type:'GET',
url:"{{ route('get.data.by.id') }}",
data:{'test_id':testId},
success:function(data){
console.log(data);
}
});
});
In your controller's getData() function just use Laravel Request to fetch the data.
public function getData(Request $request)
{
// You can return the ID to see if the ajax is working
return $request->test_id;
}

Make it post from Get for easier
At Web.php
Route::post('/list/plots', 'PlotController#getData')->name('getData');
At Blade file Ajax Request :
$(document).ready(function() {
$('#sel_test').change(function() {
var testId = $(this).val();
var url = '{{ route("getData")}}';
var token = "{{ csrf_token()}}";
$.ajax({
method:"post",
url: url,
data:{testId:testId,_token:token}
dataType: 'json',
success: function(response) {
console.log("success",response);
}
});
});
});
At Controller :
public function getData(Request $request){
$testId = $request->testId;
// Write your logic here
}
Try this. Hopefully work for you

Jsonresult is failing with parameter in my Ajax Call. Why is it happening?

That's my script on my view.
$(function () {
$('#buttonx').on("click", function (e) {
e.preventDefault();
$.ajax({
url: 'Ficha/VerificarPatrocinador',
contentType: 'application/json; charset=utf-8',
type: 'GET',
dataType: 'json',
data: {i: 100036},
success: function (data) {
$(data).each(function (index, item) {
//$('#NomePatr').append(item.Nome)
$("#NomePatr").val(item.Nome);
});
}
});
});
});
</script>
That's my action on my controller.
public JsonResult VerificarPatrocinador(int i)
{
var db = new FMDBEntities();
db.Configuration.ProxyCreationEnabled = false;
db.Configuration.LazyLoadingEnabled = false;
var consulta = db.Tabela_Participante.Where(p => p.ID_Participante == i);
return Json(consulta.
Select(x => new
{
Nome = x.Nome
}).ToList(), JsonRequestBehavior.AllowGet);
}
I'm a newbie in Ajax/Jquery, when I exclude the parameter it is ok, however, when I try to put the data: {i: 100036} in my script and the parameter in my action. It doesn't work. Why is it happening?
The controller is going fine. The parameter even passes, but I can't return this result in my View.
Thank you.

use [HttpPost] attribute on your controller method
[HttpPost]
public JsonResult VerificarPatrocinador(int i)
{
//Write Your Code
}
and change the ajax type attribute from "GET" to "POST" and use JSON.stringify. Also check the url carefully. your ajax should look like this
$(function () {
$('#buttonx').on("click", function (e) {
e.preventDefault();
$.ajax({
url: 'Ficha/VerificarPatrocinador',
contentType: 'application/json; charset=utf-8',
type: 'POST',
dataType: 'json',
data: JSON.stringify({i: 100036}),
success: function (data) {
$(data).each(function (index, item) {
//$('#NomePatr').append(item.Nome)
$("#NomePatr").val(item.Nome);
});
}
});
});
});
Hope it will help you

I think that #StephenMuecke may be on to something, because I was able to reproduce the (intended) logic with a new project.
The first thing to determine is where the code is going wrong: the server or the client.
Try using the Visual Studio debugger, and placing a breakpoint in VerificarPatrocinador. Then run the client code to see if the breakpoint is hit. When this succeeds, this means the problem is on the client end.
From there use the web browser's debugger in order to determine what is happening. Use the .fail function on the return result from .ajax in order to determine if there was a failure in the HTTP call. Here is some sample code that you can use to analyze the failure:
.fail(function (jqXHR, textStatus, errorThrown) {
alert(textStatus);
});
For more information check out http://api.jquery.com/jquery.ajax/

Change following code when ajax success
$.each(data, function (index, item) {
$("#NomePatr").val(item.Nome);
});
because when you are getting data as object of array, array or collection you can iterate using this syntax and then you can pass to var,dom...and so on where you want to display or take.
jQuery.each() means $(selector).each() you can use for dom element like below syntax: for example
<ul>
<li>foo</li>
<li>bar</li>
</ul>
<script>
$("li").each(function( index ) {
console.log( index + ": " + $( this ).text() );
});
</script>
Using GET is working fine but if it is not secure because data is visible to user when it submit as query string.
while post have
Key points about data submitted using HttpPost
POST - Submits data to be processed to a specified resource
A Submit button will always initiate an HttpPost request.
Data is submitted in http request body.
Data is not visible in the url.
It is more secured but slower as compared to GET.
It use heap method for passing form variable
It can post unlimited form variables.
It is advisable for sending critical data which should not visible to users
so I hope you understand and change ajax type:'GET' to 'POST' if you want.
$.each() and $(selector).each()

Change this line
url: 'Ficha/VerificarPatrocinador'
to:
url: '/Ficha/VerificarPatrocinador'
Because when you use this url "Ficha/VerificarPatrocinador", it will call the API from url: current url + Ficha/VerificarPatrocinador,so it isn't correct url.

Binding table in MVC 4 after Ajax call

I have an HTML able, which I bind by using the following Action in MVC controller:
public ActionResult BindTable(int ? page)
{
int pageSize = 4;
int pageNumber = 0;
List<Users> _users = query.ToList();
return View(_users.ToPagedList(pageNumber, pageSize));
}
Below the table I have the following HTML:
<textarea class="form-control" style="resize:none;" rows="9" placeholder="Enter value here..." id="txtValue"></textarea>
<br />
<button style="float:right; width:100px;" type="button" onclick="CallFunction()" class="btn btn-primary">Update specific record</button>
The Javascript function responsible for calling the action is as following:
function CallFunction() {
if ($('#txtValue').val() !== '') {
$.ajax({
url: '/User/UpdateUser',
type: 'POST',
data: { txt: $('#txtValue').val() },
success: function (data) {
$('#txtValue').val('');
alert('User updated!');
},
error: function (error) {
alert('Error: ' + error);
}
});
}
And here is the Action responsible for updating the user:
public ActionResult UpdateUser(string txtValue)
{
var obj = db.Odsutnost.Find(Convert.ToInt32(1));
if(obj!=null)
{
obj.Text= txtValue;
obj.Changed = true;
db.SaveChanges();
return RedirectToAction("BindTable");
}
return RedirectToAction("BindTable");
}
Everything works fine. But the table doesn't updates once the changes have been made ( it doesn't binds ?? )...
Can someone help me with this ???
P.S. It binds if I refresh the website.. But I want it to bind without refreshing the website...
I created a BIND function with Javascript, but it still doesn't binds:
function Bind() {
$(document).ready(function () {
var serviceURL = '/User/BindTable';
$.ajax({
type: "GET",
url: serviceURL,
contentType: "application/json; charset=utf-8",
});
});
}

You're not actually updating the page after receiving the AJAX response. This is your success function:
function (data) {
$('#txtValue').val('');
alert('User updated!');
}
So you empty an input and show an alert, but nowhere do you modify the table in any way.
Given that the ActionResult being returned is a redirect, JavaScript is likely to quietly ignore that. If you return data, you can write JavaScript to update the HTML with the new data. Or if you return a partial view (or even a page from which you can select specific content) then you can replace the table with the updated content from the server.
But basically you have to do something to update the content on the page.
In response to your edit:
You create a function:
function Bind() {
//...
}
But you don't call it anywhere. Maybe you mean to call it in the success callback?:
function (data) {
$('#txtValue').val('');
Bind();
alert('User updated!');
}
Additionally, however, that function doesn't actually do anything. For starters, all it does is set a document ready handler:
$(document).ready(function () {
//...
});
But the document is already loaded. That ready event isn't going to fire again. So perhaps you meant to just run the code immediately instead of at that event?:
function Bind() {
var serviceURL = '/User/BindTable';
$.ajax({
type: "GET",
url: serviceURL,
contentType: "application/json; charset=utf-8",
});
}
But even then, you're still back to the original problem... You don't do anything with the response. This AJAX call doesn't even have a success callback, so nothing happens when it finishes. I guess you meant to add one?:
function Bind() {
var serviceURL = '/User/BindTable';
$.ajax({
type: "GET",
url: serviceURL,
contentType: "application/json; charset=utf-8",
success: function (data) {
// do something with the response here
}
});
}
What you do with the response is up to you. For example, if the response is a completely new HTML table then you can replace the existing one with the new one:
$('#someParentElement').html(data);
Though since you're not passing any data or doing anything more than a simple GET request, you might as well simplify the whole thing to just a call to .load(). Something like this:
$('#someParentElement').load('/User/BindTable');
(Basically just use this inside of your first success callback, so you don't need that whole Bind() function at all.)
That encapsulates the entire GET request of the second AJAX call you're making, as well as replaces the target element with the response from that request. (With the added benefit that if the request contains more markup than you want to use in that element, you can add jQuery selectors directly to the call to .load() to filter down to just what you want.)

jQuery pass parameters into function call from ajax success

I want to call a function when a jQuery Ajax request is successfull. I want to pass a parameter into a second function that apparently (it doesn't work) doesn't exist inside the jquery anonymous function.
Here is my Ajax function:
function core_get_title(url,id_of_link){
$.ajax({
type: "POST",
url: "url_handler.php",
data: {
url: url,
cmd: "get_title",
},
success: function(data) {
core_title_auto(data,id_of_link);
}
});
}
And when it calls core_title_auto, the id_of_link parameter is empty.
Any ideas?

check and see whats in id_of_link before ajax call by placing an alert function
function core_get_title(url,id_of_link){
alert("id_of_link"+id_of_link);
$.ajax({
/*...... your code */
});
}