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Ajax: conflict in client between two functions

For a university homework, I have to create a little e-commerce website.
After the login, the user is redirected to the homepage. In this homepage, the client will recive a JSON object from the server (containing some product to be loaded) to generate the DOM of the homepage dynamically.
Note: I must use AJAX and JSON
I have this client.js file:
$(document).ready(function() {
// AJAX request on submit
$("#login_form").submit(function (e) {
e.preventDefault();
$.ajax({
type: "POST",
url: "submit.php",
data: {
Email: document.getElementById('login_email').value, // Email in the form
Password: document.getElementById('login_password').value // // Password in the form
},
cache: false,
success: function(){
window.location.href = "home.php"; // load the home.php page in the default folder
}
});
});
});
$(document).ready(function() {
// AJAX request to open a channel between php and client
function (e) {
e.preventDefault();
$.ajax({
type: "GET",
url: "queries.php",
dataType: "json",
success: function(data){
var data = JSON.parse(data);
alert(data); // debug
showProducts(data);
});
});
});
});
function showProducts(data){
alert(data);
// Insert object into the page DOM
}
I don't know why, but I can't access after the login if the second Ajax request (the AJAX request to open a channel between php and client) is not commented, and I don't know why, because the code seems right... Any suggestion?

after login action you need to set to cookie token in response
success: function(response){
console.log(response)
// then set to cookie response.token
window.location.href = "home.php";
}
after set token to cookie, you need to send this token to next ajax request url: "queries.php",

You need to wrap your anonymous function in parenthesis and add () at the end if you want to execute it:
(function (e) {
// I don't know why you need this:
e.preventDefault();
// etc.
})();
You should also check the contents of that function as you seem to have too many closing parentheses and you don't need to parse the returned value if you set the dataType to json.
In the end I think this is about all you need for that function:
(function () {
$.ajax({
type: "GET",
url: "queries.php",
dataType: "json",
success: function(data){
console.log(data); // debug
showProducts(data);
}
});
})();
or just:
$.ajax({
type: "GET",
url: "queries.php",
dataType: "json",
success: function(data){
console.log(data); // debug
showProducts(data);
}
});
To get it directly on page load.

Ajax callback to check variables as global

I'm trying to implement a function that after consulting a service brings the variables as global.
function ajax_test(str1, callback){
$.ajax({
url: '/path/service',
type: 'POST',
dataType: "json",
data: {'vars':$('form').serialize(), 'test':123},
success: function(data, status, xhr){
callback(data);
}
});
}
and I'm trying to call like this:
ajax_test("str", function(url) {
//do something with url
console.log(url);
});
Now, if I just call ajax_test() it returns an error, saying that callback is not a function.
How would be the best way to simply call the function and get the results to use global variables?
Edit:
I think a good question is: what is a good alternative to async: false? How is the best way to implement synchronous callback?
Edit 2:
For now, I'm using $.post() with $.ajaxSetup({async: false}); and it works how I expect. Still looking a way I could use with a callback.

Have to set the scope inside the success method. Adding the following should work.
function ajax_test(str1, callback){
$.ajax({
url: '/path/service',
type: 'POST',
dataType: "json",
data: {'vars':$('form').serialize(), 'test':123},
success: function(data, status, xhr){
this.callback(data);
}.bind(this)
});
}

As an argument of the ajax_test function, callback is in the scope of the ajax_test function definition and can be called anywhere there, particularly in the successcase. Note that calling ajax_test() without arguments will as expected make your code call a function that does not exist, named callback.
The following sends an Ajax request to the jsFiddle echo service (both examples of callback as anonymous or global function are given in the jsFiddle), and works properly :
function ajax_test(str1, callback){
$.ajax({
url: '/echo/json',
type: 'POST',
dataType: "json",
data: {
json: JSON.stringify({
'vars':$('form').serialize(),
'test':123
})
},
success: function(data, status, xhr){
callback(data);
}
});
}
ajax_test("unusedString", function(data){
console.log("Callback (echo from jsFiddle called), data :", data);
});
Can you check that the webservice you're calling returns successfully ? Here is the jsFiddle, I hope you can adapt it to your need :
https://jsfiddle.net/dyjjv3o0
UPDATE: similar code using an object
function ajax_test(str1) {
this.JSONFromAjax = null;
var self = this;
function callback(data) {
console.log("Hello, data :", data);
console.log("Hello, this :", this);
$("#callbackResultId").append("<p>Anonymous function : " + JSON.stringify(data) + "</p>");
this.JSONFromAjax = JSON.stringify(data);
}
$.ajax({
url: '/echo/json',
type: 'POST',
dataType: "json",
data: {
json: JSON.stringify({
'vars': $('form').serialize(),
'test': 123
})
},
success: function(data, status, xhr) {
console.log("Success ajax");
// 'self' is the object, force callback to use 'self' as 'this' internally.
// We cannot use 'this' directly here as it refers to the 'ajax' object provided by jQuery
callback.call(self, data);
}
});
}
var obj = new ajax_test("unusedString");
// Right after the creation, Ajax request did not complete
console.log("obj.JSONFromAjax", obj.JSONFromAjax);
setTimeout(function(){
// Ajax request completed, obj has been updated
console.log("obj.JSONFromAjax", obj.JSONFromAjax);
}, 2000)
You cannot expect the Ajax request to complete immediately (don't know how it behaves with async: false though, this is why you need to wait for a while before getting the actual response.
Updated jsFiddle here : http://jsfiddle.net/jjt39mg3
Hope this helps!

How to pass a variable from ajax to nested ajax

I'm sending ajax call and getting an answer that I need from the first ajax then I want to pass my result to my nested ajax, my var (result) is null in the nested ajax/settimeout fun, can I pass it ? Am I missing something ?
$.ajax({
url: '#Url.Action("getCustomerGuidId", "Document")',
type: 'POST',
cache: false,
data: { "classNum": currentclassNum},
contentType:'json' ,
dataType:'text',
success: function (result) {
alert(result);**-> is fine - not null**.
// a or result is null when I hit the getCurrentDoc- function althought I get the data I need from getCustomerGuidId function
var a = result;-> tried to pass it to a new var..IDK.. I
thought it will help... it didn't.
setTimeout(function () {
$.ajax({
type: "GET",
url: '#Url.Action("getCurrentDoc", "Document")',
contentType:'text',
data: a,-> here it's null
success: function (data) {
}
});
}, 2000);
},
error: function (result) {
alert("fail " + result);
}
});

You can try something like this will help to pass value to nested ajax call
function test(){
var myText = 'Hello all !!';
$.get({
//used the jsonplaceholder url for testing
'url':'https://jsonplaceholder.typicode.com/posts/1',
'method':'GET',
success: function (data) {
//updating value of myText
myText = 'welcome';
$.post({
'url':'https://jsonplaceholder.typicode.com/posts',
'method':'POST',
//data.title is the return value from get request to the post request
'data':{'title':data.title},
'success':function (data) {
alert(data.title +'\n' + myText);//your code here ...
}
});
}
});
}

An old question and you've likely moved on, but there's still no accepted answer.
Your setTimeout takes an anonymous function, so you are losing your binding; if you have to use a Timeout for some reason, you need to add .bind(this) to your setTimeout call (see below)
setTimeout(function () {
$.ajax({
type: "GET",
url: '#Url.Action("getCurrentDoc", "Document")',
contentType:'text',
data: a,
success: function (data) {
}
});
}.bind(this), 2000);
At a guess you're using a Timeout because you want to ensure that your promise (i.e. the first ajax call) is resolving prior to making the nested call.
If that's your intention, you can actually scrap setTimeout completely as you have the nested call in the first ajax success call, which only runs once the promise has been resolved (providing there isn't an error; if so, jQuery would call error rather than success)
Removing setTimeout means you won't lose your binding, and a should still be result (hopefully a is an object, otherwise your second call is also going to experience issues...)
Lastly, after overcoming the binding issue you wouldn't need var a = result; you should be able to pass result directly to your nested ajax call.
Good luck!

In the nested ajax you send a as a param name, not as a param value.
So you can try the following (change param to actual param name which your server expects):
$.ajax({
url: '#Url.Action("getCustomerGuidId", "Document")',
type: 'POST',
cache: false,
data: { "classNum": currentclassNum},
dataType:'text',
success: function (result) {
setTimeout(function () {
$.ajax({
type: "GET",
url: '#Url.Action("getCurrentDoc", "Document")',
data: {param: result},
success: function (data) {
}
});
}, 2000);
},
error: function (result) {
alert("fail " + result);
}
});

how to use ajax response data in another javascript

I am working with google map.My map data come from php using ajax response.
My ajax code:
<script type="text/javascript">
$.ajax({
type: "POST",
url: "mapajax.php",
dataType:'text',
success: function (result) {
console.log(result);
}
});
</script>
Now I have need to put my response data in my map var location
function initialize() {
var locations = [
//Now here I put my ajax response result
];
How can I do that?

You'll have to refactor your code a little. I'm assuming you call initialize from the success callback.
Pass the locations array as an argument to initialize.
function initialize(locations) { ... }
$.ajax({
type: "POST",
url: "mapajax.php",
dataType:'text',
success: function (result) {
initialize(result);
}
});
Then you can cut down even more and just do success: initialize, as long as initialize doesn't expect other parameters.

Here is a fiddle with an example using $.when but its for SYNTAX only not making the call
http://jsfiddle.net/2y6689mu/
// Returns a deferred object
function mapData(){ return $.ajax({
type: "POST",
url: "mapajax.php",
dataType:'text'
});
}
// This is the magic where it waits for the data to be resolved
$.when( mapData() ).then( initialize, errorHandler );
EDIT** function already returns a promise so you can just use
mapData().then()
per code-jaff comments

This is done using callbacks, http://recurial.com/programming/understanding-callback-functions-in-javascript/ , here's a link if you want to read up on those. Let's see your current code here:
<script type="text/javascript">
$.ajax({
type: "POST",
url: "mapajax.php",
dataType:'text',
success: function (result) {
console.log(result);
}
});
</script>
As you noticed, the 'result' data is accessible in the success function. So how do you get transport it to another function? You used console.log(result) to print the data to your console. And without realizing it, you almost solved the problem yourself.
Just call the initialize function inside the success function of the ajax call:
<script type="text/javascript">
$.ajax({
type: "POST",
url: "mapajax.php",
dataType:'text',
success: function (result) {
initialize(result);
}
});
</script>

Is expected dataType response from $.ajax() to mapajax.php call text ?
Try
$(function () {
function initialize(data) {
var locations = [
//Now here I put my ajax response result
];
// "put my ajax response result"
// utilizing `Array.prototype.push()`
locations.push(data);
// do stuff
// with `locations` data, e.g.,
return console.log(JSON.parse(locations));
};
$.ajax({
type: "POST",
url: "mapajax.php",
dataType: 'text',
success: function (result) {
initialize(result);
}
});
});
jsfiddle http://jsfiddle.net/guest271314/maaxoy91/
See
https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/push

Calling a PHP script using ajax

hi i am calling a php file using ajax after an interval of time. In my php file i simply echo a text line. But it didnt show me any output after time interval..
here is my ajax code form where i am calling my php file..
<script>
$(document).ready(function() {
setTimeout(function() {
$.ajax({
url: 'process.php',
type: 'post',
data: {"token": "your_token"}, });
}, 5000);
});
</script>
code inside the process.php file
<?php
echo "hello testing";
?>

You aren't handling the response from php script. You need to get it by success parameter in ajax. Try this:
$(document).ready(function() {
setTimeout(function() {
$.ajax({
url: 'process.php',
type: 'post',
data: 'x=1&y=2', // data here! use query strings like this or;
// data: { x: '1', y: '2' }
success: function(response) { alert(response); } // alert the response text
// returns 'hello testing'
error: function(){ alert('error while posting data'); }
});
}, 5000);
});

User the success and error function of ajax. for eg
$.ajax ({
url: 'process.php',
type:'post'
data:data1,
success: function (response) {
//alert response here you will get the value hello testing
alert (response);
},
error {
alert ('error');
}
});

You should modify your code to use the response.
<script>
$(document).ready(function() {
setTimeout(function() {
$.ajax({
url: 'process.php',
type: 'post',
data: {"token": "your_token"},
success:function(str){
$("#YOUR_ELEMENT").html(str);
}
});
}, 5000);
});

Just change your JQuery script to show the response after successful request it can be done with done() or success functions.
<script>
$(document).ready(function() {
setTimeout(function() {
$.ajax({
url: 'process.php',
type: 'post',
data: { token: "your_token"}}).done(function(msg){
$("#response").append(msg);
};
}, 5000);
});
This will append reponses to #response every 5s when ajax request is successful.

the success block, which handles the data returned from remote script is present in your code. you may need to add something like this .
JS CODE:
$(document).ready(function() {
setTimeout(function() {
$.ajax({
url: 'process.php',
type: 'post',
data: {"token": "your_token"},
}).done(function( data) {
//data received from remote script
});
}, 5000);
});
Happy Coding :)

Timeout is not the culprit here.
We need to make sure that you have a server where process.php resides and its running fine.
Make sure the path for the file process.php is right. You can use browser's developer tools. When the request is made you will see a new entry under "Network" tab of the developer tools. Exploring it you can get the url at which it the file should be available.
I would suggest using Google Chrome's "postman" extension to test the ajax call before implementing it in your code.
Also you need to have a callback that will run in case of request success or failure. Once you get the string in success response, you can do whatever you intend to do with it.
<script>
$(document).ready(function() {
setTimeout(function() {
$.ajax({
url: 'process.php',
type: 'post',
data: {"token": "your_token"} //removed the comma from last argument
}).done(function(serverResponse) {
alert( "Success: " + serverResponse ); //Will show success alert with concatenated text string if the request is successful
}).fail(function(serverResponse) {
alert( "Error: " + serverResponse.message); //Will show error alert with concatenated error message
});
}, 5000);
});
</script>

the php page sends the string "hello testing", and you have to manage it.
take a look here for an example: click me