Changing global variables in a ajax call - javascript

I've been trying to get this right for quite some time, I'm trying to append the object from the first ajax call after the second ajax call. But the for loop seems to iterate the changing of the value to the last result before appending the information, having the last post appended every time.
var scribjson =
{
"user_id" : localStorage.viewing,
};
scribjs = JSON.stringify(scribjson);
var scrib = {json:scribjs};
$.ajax({
type: "POST",
url: "getScribbles.php",
data: scrib,
success: function(result)
{
var obj = jQuery.parseJSON(result);
for(var i = 0; i < obj.length; i+=1)
{
var userjson =
{
"user_id" : obj[i].user_id
};
userjs = JSON.stringify(userjson);
var user = {json:userjs};
localStorage.post = obj[i].post;
$.ajax({
type: "POST",
url: "getRequestsInfo.php",
data: user,
success: function(result)
{
var obj2 = jQuery.parseJSON(result);
$('#listOfScribbles').append("<tr><td><img id = 'small_pic' src = '" + obj2[0].profileImage + "'/></td><tr><td>" + obj2[0].firstname + " " + obj2[0].lastname + "</td></tr> ");
$('#listOfScribbles').append("<tr><td>" + obj[i].post + "</td></tr>");
},
error: function()
{
alert('An Error has occured, please try again.');
}
});
}
},
error: function()
{
alert('An Error has occured, please try again.');
}
});

Since ajax calls It looks like the all success functions of the inner ajax call are being called after the loop has ended, so i will always be the last iterated value.
Try this:
(function(i)
{
$.ajax({
type: "POST",
url: "getRequestsInfo.php",
data: user,
success: function(result)
{
var obj2 = jQuery.parseJSON(result);
$('#listOfScribbles').append("<tr><td><img id = 'small_pic' src = '" + obj2[0].profileImage + "'/></td><tr><td>" + obj2[0].firstname + " " + obj2[0].lastname + "</td></tr> ");
$('#listOfScribbles').append("<tr><td>" + obj[i].post + "</td></tr>");
},
error: function()
{
alert('An Error has occured, please try again.');
}
});
})(i);
This will create a closure on i, which will give each ajax call its own copy of the current value.

Use an IIFE:
success: (function(i){return function(result) {
var obj2 = jQuery.parseJSON(result);
$('#listOfScribbles').append("<tr><td><img id = 'small_pic' src = '" + obj2[0].profileImage + "'/></td><tr><td>" + obj2[0].firstname + " " + obj2[0].lastname + "</td></tr> ");
$('#listOfScribbles').append("<tr><td>" + obj[i].post + "</td></tr>");
}})(i),
etc. Currently your loop generated ajax success handlers contain a direct reference to the counter itself, which (by the time they are called) has reached its final value.

Related

GET Method always receives null value

I´m trying to get a list with Ajax when a modal shows up, but for some reason my method always receives a null variable. I´m sure that the issue is on the Ajax call, because if I test my method using 1 as an argument instead of the value from Ajax, it returns the list the way I wanted.
JS:
$("#visualizacao").on('show.bs.modal', function (e) {
var data = $(e.relatedTarget);
var idAviso = data.context.dataset.avisoid;
$.ajax({
type: 'GET',
url: 'ListaVisuAviso/' +idAviso,
success: function (response) {
$('#visu-table tbody').empty();
var trHTML = '';
$.each(response, function (i, item) {
trHTML += '<tr><td>' + item.NOME + '</td><td>' + item.DATA_HORA + '</td><td>' + item.DEPARTAMENTO + '</td></tr>';
});
$('#visu-table tbody').append(trHTML);
$('#modal-visu').modal('show');
},
error: function (xhr) {
console.log(xhr);
}
});
$('#modalAviso').modal('show');
});
C#
[HttpGet]
public JsonResult ListaVisuAviso(string avisoId)
{
//var avisoid = 1;
var avisoid = Convert.ToDecimal(avisoId);
var query =
from a in _dataContext.TB_AVISOS_NOTIFICACOES
join b in _dataContext.VW_USUARIOS4 on a.USUARIO_PR equals b.USUARIOID
where a.AVISO_ID == avisoid
select new VisuAviso()
{
NOME = b.NOME,
DATA_HORA = a.DATA_HORA.ToString(),
DEPARTAMENTO = b.DEPARTAMENTO
};
return Json(query, JsonRequestBehavior.AllowGet);
}
I discovered what was causing the "issue". To use this way of sending the parameter, my route config on the backend was expecting it to be a parameter called "id". So I would either change my receiving parameter to "id" instead of "avisoId" like the following:
[HttpGet]
public JsonResult ListaVisuAviso(string id)
{
//var avisoid = 4;
var avisoid = Convert.ToDecimal(id);
var query =
from a in _dataContext.TB_AVISOS_NOTIFICACOES
join b in _dataContext.VW_USUARIOS4 on a.USUARIO_PR equals b.USUARIOID
where a.AVISO_ID == avisoid
select new VisuAviso()
{
NOME = b.NOME,
DATA_HORA = a.DATA_HORA.ToString(),
DEPARTAMENTO = b.DEPARTAMENTO
};
return Json(query, JsonRequestBehavior.AllowGet);
Or, I would have do specify the name of the parameter on the JS, like this "?usuarioId=", this way the route would know that it´s not the id parameter:
$("#visualizacao").on('show.bs.modal', function (e) {
var idAviso = $(e.relatedTarget).attr('data-avisoid');
$.ajax({
type: 'GET',
url: 'ListaVisuAviso/?usuarioId =' + idAviso,
dataType: 'json',
success: function (response) {
$('#visu-table tbody').empty();
var trHTML = '';
$.each(response, function (i, item) {
trHTML += '<tr><td>' + item.NOME + '</td><td>' + item.DATA_HORA + '</td><td>' + item.DEPARTAMENTO + '</td></tr>';
});
$('#visu-table tbody').append(trHTML);
$('#modal-visu').modal('show');
},
error: function (xhr) {
console.log(xhr);
}
});
$('#modalAviso').modal('show');
});

keep the memory of more than one index

I have more than three TextBoxes. I want to send this data as in the code. The "indeks " value is always the last click. How do I keep the index?
click:function(e) {
var item = e.itemElement.index();
indeks = item;
}
var field= "";
onl: function () {
$.ajax({
type: "GET",
cache:true,
url: MYURL,
success: function (msg, result, status, xhr) {
var obje = jQuery.parseJSON(msg)
var i = 0;
field = " ";
$('#wrapper *').filter(':input').each(function () {
if (txtvalue != "") {
if (i)
field += " and ";
field = field + "[" + obje[indeks]+ "]" $(this ).val() + "'";
i++;
}
});
});
},
As I wasn't sure if I got your question right, I prefered to comment on your topic - but now it seems that my answer helped you, so I decided to post it as an actual answer:
1st step: declare an array outside your success handler
2nd step: push the index and the value for the element into this array
3rd step: loop through all entries of the array and build your 'select' statement
Here is your edited example:
https://jsfiddle.net/Lk2373h2/1/
var clickedIndexes = [];
click:function(e) {
var item = e.itemElement.index();
indeks = item;
}
var field= "";
onl: function () {
$.ajax({
type: "GET",
cache:true,
url: MYURL,
success: function (msg, result, status, xhr) {
var obje = jQuery.parseJSON(msg)
var i = 0;
field = " ";
$('#wrapper *').filter(':input').each(function () {
$(this).attr('id', i);
var txtvalue=$(this).val();
if (i)
clickedIndexes.push({
index: indeks,
value: $(this ).val()
});
var selectString = "";
for (var u = 0; u < clickedIndexes.length; u++) {
selectString += "[" + obje[clickedIndexes[u].index].ALAN + "]" + "=" + "'" + clickedIndexes[u].value + "'";
}
field = selectString;
i++;
});
});
},

Index of an array becomes undefined while looping [duplicate]

This question already has answers here:
Javascript infamous Loop issue? [duplicate]
(5 answers)
Closed 8 years ago.
I am creating a small domain availability checker. For that I will parse the desired domain into a form, and submit that to a PHP file with jQuery AJAX.
However while I am looping through the different TLD's it suddenly gets undefined and I am not able to use the "TLD" for further processing within the loop. As far as I can read, it as something to do with the loop happening first and the requests made after, so I somehow have to freeze the index of my array. But I don't know how to do that.
This is my code:
$("input[name=submit]").click(function(){
var getDomain = $("#domainsearch").val();
var stripDomain = getDomain.split(".");
var domain = stripDomain[0];
var tlds = ["dk", "se", "com", "net"];
for (var i = 0; i < tlds.length; i++ ) {
var dataString = "domain=" + domain + "." + tlds[i];
console.log(dataString);
$.ajax({
type: "POST",
url: "search.php",
data: dataString,
success: function(data) {
console.log(domain + "." + tlds[i] + " is " + data);
}
});
};
return false;
});
The printed console.log's looks like this:
This is a classic JavaScript issue. In the success function (a closure), the i is being used. That callback runs in the future, once the AJAX call is done. By that point, the loop has finished, and i has been incremented to 4.
tlds[4] doesn't exist, and that's why you're getting undefined. The callbacks are all using the same i value.
To fix it, you need to create a new function to capture the value of i for each callback.
$("input[name=submit]").click(function(){
var getDomain = $("#domainsearch").val();
var stripDomain = getDomain.split(".");
var domain = stripDomain[0];
var tlds = ["dk", "se", "com", "net"];
var createCallback = function(i){
return function(data) {
console.log(domain + "." + tlds[i] + " is " + data);
};
}
for (var i = 0; i < tlds.length; i++ ) {
var dataString = "domain=" + domain + "." + tlds[i];
console.log(dataString);
$.ajax({
type: "POST",
url: "search.php",
data: dataString,
success: createCallback(i)
});
};
return false;
});
By the time the ajax calls return, the loop has long since ended, and i has run past the end of tlds. Trying to print tlds[i] is bound to fail.
Break the lookup into a separate function, with local variables that will be valid on the ajax callback:
var checkup = function(datastring, domain, tld) {
$.ajax({
type: "POST",
url: "search.php",
data: dataString,
success: function(data) {
console.log(domain + "." + tld + " is " + data);
}
});
};
for (var i = 0; i < tlds.length; i++ ) {
var dataString = "domain=" + domain + "." + tlds[i];
console.log(dataString);
checkup(datastring, domain, tlds[i]);
};
You need to enclose the code in your loop in a closure as follows:
$("input[name=submit]").click(function(){
var getDomain = $("#domainsearch").val();
var stripDomain = getDomain.split(".");
var domain = stripDomain[0];
var tlds = ["dk", "se", "com", "net"];
for (var i = 0; i < tlds.length; i++ ) {
(function() {
var dataString = "domain=" + domain + "." + tlds[i];
console.log(dataString);
$.ajax({
type: "POST",
url: "search.php",
data: dataString,
success: function(data) {
console.log(domain + "." + tlds[i] + " is " + data);
}
});
})( i );
}
return false;
});

Document.Ready function doesn't seem to be working

Right now I have username and password saved in cookies. My goal is to send that data to my server and then the server will send back response and I will display the response on my webpage. But before I do that I used alert() to see if it is working.
I think something is wrong with the JS:
$(document).ready(function () {
var messageType = "3";
var cookie_name = "username";
var cookie_name2 = "password";
var YouWrote = getName(cookie_name);
var YouWrote2 = getName2(cookie_name2);
var userName = YouWrote;
var password = YouWrote2;
auth(messageType, userName, password);
});
function auth(messageType, userName, password) {
$.ajax({
type: "POST",
//SEND TO SERVER URL
url: "######",
dataType: 'json',
async: false,
data: '{"messageType": "' + messageType + '", "userName": "' + userName + '", "password" : "' + password + '"}',
error: function (xhr, error) {
alert('Error!');
},
success: function (data, textStatus, jqXHR) {
alert(data.details + '\nHello ' + data.clientInfo.firstName + ' ' + data.clientInfo.lastName + '. \nBalance:' + data.clientInfo.balance);
}
})
}
These two functions will help me get the cookie data saved (this works, I have tested it):
function getName() {
if (document.cookie) {
index = document.cookie.indexOf(cookie_name);
if (index != -1) {
namestart = (document.cookie.indexOf("=", index) + 1);
nameend = document.cookie.indexOf(";", index);
if (nameend == -1) {
nameend = document.cookie.length;
}
YouWrote = document.cookie.substring(namestart, nameend);
return YouWrote;
}
}
}
function getName2() {
if (document.cookie) {
index = document.cookie.indexOf(cookie_name2);
if (index != -1) {
namestart = (document.cookie.indexOf("=", index) + 1);
nameend = document.cookie.indexOf(";", index);
if (nameend == -1) {
nameend = document.cookie.length;
}
YouWrote2 = document.cookie.substring(namestart, nameend);
return YouWrote2;
}
}
}
I turned my server off on purpose because I want to see if it will show alert("Error!"). It doesn't which means the functions aren't running properly in the document.ready.
Is there an obvious issue that I'm missing? Any help will be much appreciated.
Your functions will need to have input argument specified:
function getName(cookie_name){ ... };
function getName2(cookie_name2){ ... };

populated jquery objects show as undefined when passed

In the following script, although the two weather objects are both populated with data in the ajax calls, the updateWeather call shows them both as undefined prior to that line executing. I moved the variable declarations so they would be global but they still both show undefined prior to the updateWeather call. What am I missing? Can I not set up a variable in the ajax success function and then pass it later?
Note: If you want to test this use a different url as this one won't work for you with out my credentials
function getWeatherForecastStationCode() {
var d = new Date();
var parts = d.toString().split(" ");
var dDate = parts[1] + " " + parts[2] + ", " + parts[3];
var ampm;
if (parts[4].split(":")[0] <= 12) {
ampm = "AM";
} else {
ampm = "PM";
}
var dtime = parts[4].split(":")[0] + ":" + parts[4].split(":")[1];
var datetime = dDate + " " + dtime + ampm;
alert(datetime);
var weatherStation = "KPBI"; // get from GetWeatherService.svc
var forecastFields = "&fields=periods.maxTempF%2cperiods.minTempF%2cperiods.vaildTime%2cperiods.weather%2cperiods.icon";
var currentFields = "&fields=ob.tempC%2cob.tempF%2cob.icon%2cplace.name%2cplace.state";
var forecastUrlWeatherStation = 'http://api.aerisapi.com/forecasts/' + weatherStation + '?limit=1&client_id=' + AerisClientId + '&client_secret=' + AerisWeatherApiSecret + forecastFields;
var currentUrlWeatherStation = 'http://api.aerisapi.com/observations/' + weatherStation + '?limit=1&client_id=' + AerisClientId + '&client_secret=' + AerisWeatherApiSecret + currentFields;
$.ajax({
type: "GET",
url: forecastUrlWeatherStation,
dataType: "json",
success: function (json) {
if (json.success === true) {
forecastedWeather = {
weather: json.response[0].periods[0].weather,
maxTemp: json.response[0].periods[0].maxTempF,
minTemp: json.response[0].periods[0].minTempF,
weatherIcon: json.response[0].periods[0].icon,
obsTime: datetime
};
}
else {
alert('An error occurred: ' + json.error.description);
}
}
});
var location;
$.ajax({
type: "GET",
url: currentUrlWeatherStation,
dataType: "json",
success: function (json) {
if (json.success === true) {
var place = json.response.place.name.split(" ");
if (place.length === 1) {
location = place[0].charAt(0).toUpperCase() + place[0].substr(1, place[0].length);
} else {
location = place[0].charAt(0).toUpperCase() + place[0].substr(1, place[0].length) + " " + place[1].charAt(0).toUpperCase() + place[1].substr(1, place[1].length) + ", " + json.response.place.state.toUpperCase();
}
currentWeather = {
location: location,
currentTemp: json.response.ob.tempF
};
} else {
alert('An error occurred: ' + json.error.description);
}
}
});
updateWeather(forecastedWeather,currentWeather);
}
The problem is that AJAX is Asynchronous (Thats the "A" in "AJAX"), so the call to updateWeather is executing before a response is received from your 2 ajax calls.
The way to do this then, is to wait for all ajax calls to complete before calling updateWeather.
Something like the following (untested):
$.when(getForecast(),getCurrent()).done(function(f,c){
updateWeather(forecastedWeather,currentWeather)
});
function getForecast(){
return $.ajax({
type: "GET",
url: forecastUrlWeatherStation,
dataType: "json"
....
});
};
function getCurrent(){
return $.ajax({
type: "GET",
url: currentUrlWeatherStation,
dataType: "json"
....
});
};

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