Develop Reference

how to overload an array in javascript?

thsi is my code:
var data_book_list=new Array();
var test_type= jQuery('#test_type').val('list1');
function bookList() {
jQuery.ajax({
type: "POST",
url: "array.php",
dataType: 'json',
data: {book:book},
success: function(data){
for(var i=0;i<data.length;i++)
{
data_list.push(data[i]);
}
}
});
imagine database like: list1 has a1,a2,a3 & list2 b1,b2,b3
if i selected value list1 ajax get that value and sent it to php.
php using where case so it gives back to ajaxa1,a2,a3
now data has a1,a2,a3 i make it that a new array form for loop like ['a1','a2','a3']
i push this to a var data_book_list=[];
it work great.
but my problem is if i select option list2
data hasb1,b2,b3 and data_book_list=[] has a1,a2,a3
for loop push data b1,b2,b3 to array data_book_list it will extend like ['a1','a2','a3', 'b1','b2','b3']
but i need like this ['b1','b2','b3] in array data_book_list. how to clear or overload old array data automatically.

If you need to keep track of all the values retrieved so far, then you will have to use an object and have the value as array, corresponding to the keys.
var data_book_list_obj = {};
var test_type= jQuery('#test_type').val('list1');
function bookList() {
jQuery.ajax({
type: "POST",
url: "array.php",
dataType: 'json',
data: {book: test_type},
success: function(data){
for(var i=0;i<data.length;i++)
{
data_book_list_obj[test_type] = data_book_list_obj[test_type] || [];
data_book_list_obj[test_type].push(data[i]);
}
}
});
Or if you need only the recent information, then just assign the value.
var data_book_list=new Array();
var test_type= jQuery('#test_type').val('list1');
function bookList() {
jQuery.ajax({
type: "POST",
url: "array.php",
dataType: 'json',
data: {book: test_type},
success: function(data){
// Edit removed for loop wrongly put here
data_book_list = data;
}
});

Declaring global variable not working (returning undefined)

I have this basic set up and the problem I have is the variable locations_map in my function load_heat2. I indicated below where I'm getting the undefined:
//declare global variables
var full_map;
var locations_map;
function callIndex() {
$(document).ready(function() {
//call some functions
load_map();
load_test_map2();
super_test_map();
load_heat2();
});
$.ajax({
url: 'php/get_map_tables.php',
type: 'POST',
dataType: 'JSON',
data: {
client_id: client_id, //defined elsewhere
},
success: function(data) { //this gives me the correct data in the right variables
var locations_map = data[0].locations_map;
var full_map = data[0].full_map;
}
});
function load_heat2(){
console.log(locations_map); //this yields undefined
}
} //end of callIndex function
I'm trying to avoid wrapping everything in my AJAX/success function, so I need the global variable to work.
Thanks.

You're declaring a local variable called locations_map in your success statement
$.ajax({
url: 'php/get_map_tables.php',
type: 'POST',
dataType: 'JSON',
data: {
client_id: client_id, //defined elsewhere
},
success: function(data) { //this gives me the correct data in the right variables
**var** locations_map = data[0].locations_map;
var full_map = data[0].full_map;
}

You are re-declaring the two variables in the ajax function.
var full_map;
var locations_map;
This is declaring them as global but when you set them here
success: function(data) { //this gives me the correct data in the right variables
var locations_map = data[0].locations_map;
var full_map = data[0].full_map;
}
It becomes local. In order for them to remain global you need to remove the
var
so it would look like
success: function(data) { //this gives me the correct data in the right variables
locations_map = data[0].locations_map;
full_map = data[0].full_map;
}

Call the load_heat2() function after you have the response of the ajax request. Also, remove the "var" of both variables like the other answers are pointing.
//declare global variables
var full_map;
var locations_map;
function load_heat2(){
console.log(locations_map); //this yields undefined
}
function callIndex() {
$(document).ready(function() {
//call some functions
load_map();
load_test_map2();
super_test_map();
});
$.ajax({
url: 'php/get_map_tables.php',
type: 'POST',
dataType: 'JSON',
data: {
client_id: client_id, //defined elsewhere
},
success: function(data) { //this gives me the correct data in the right variables
locations_map = data[0].locations_map;
full_map = data[0].full_map;
load_heat2();
}
});
} //end of callIndex function

Javascript, create a global variable with window[]

So, i'm in an ajax request, in the success callback :
var just_id = $(this).attr('id');
$.ajax({
type: "GET",
url: "/tw/www/search/",
data: {search:tw_search, type:'tw_search'},
success: function (html) {
window[just_id] = $(this).attr('tw_username');
}
});
With this code, after i call with ajax my script, i need to create a variable with the name of a specific element.
So, if i'm on a <div id="test"></div>, in var just_id i have test and then, i create a variable test with window[just_id].
But i need to retrieve this variable in an other function on my page.. How can i do that ? I need to create a global variable with windows[]... Thanks !

Use window to declare global variable:
window.globalVar[];// i have not give window as varible name this may cause error it must be reserved
var just_id = $(this).attr('id');
$.ajax({
type: "GET",
url: "/tw/www/search/",
data: {search:tw_search, type:'tw_search'},
success: function (html) {
globalVar[just_id] = $(this).attr('tw_username');
}
});

NB! First of all, if you are using this in success callback in ajax, this would have different context, not what you are expecting.
Answer: you can define some variable in top of function declaration
var just_id = $(this).attr('id'),
attrUsername;
$.ajax({
type: "GET",
url: "/tw/www/search/",
data: {
search: tw_search,
type: 'tw_search'
},
success: function (html) {
attrUsername = $(this).attr('tw_username');
}
});
Then, you can access to this variable. Avoid to use global variable for your purpose

Can't directly assign indexed value to window object. But you can do in this way:
window.x = new Array();
window.x[4] = 'value here';
// And can read from any function like here
;(function(){
alert(window.x[4]);
})();
For your script above:
window.global = new Array();
window.global[just_id] = $(this).attr('id');
$.ajax({
type: "GET",
url: "/tw/www/search/",
data: {search:tw_search, type:'tw_search'},
success: function (html) {
window.global[just_id] = $(this).attr('tw_username');
}
});

Accessing JSONP data outside of ajax call in jQuery

Now that every google link in the first 5 pages of results is :visited in my browser, I needed to ask...
How can I get the JSON data working so that I can access it/manipulate it in other methods?
_otherMethod: function() {
// END GOAL OF WHERE I WANT THIS TO BE AVAILABLE
var text = this._requestText();
},
_requestText: function() {
var url = 'http://api.flickr.com/services/feeds/photos_public.gne?format=json';
$.ajax({
type: 'GET',
url: url,
async: false,
dataType: 'jsonp',
success: function(data) {
// works here
console.log(data);
// works here as well & fires local function
testing(data);
// doesnt store
var testvar_1 = data;
}
});
// undefined
console.log(testvar_1);
function testing(data) {
// logs when called from above
console.log(data);
// doesnt store
var testvar_2 = data;
}
// undefined
console.log(testvar_2);
// havent found this yet...
return magicVariableThatLetsMeAccessJSON
}, ...
any ideas? i know theres a lot of other similar questions on stack overflow, but i have found nothing that solves this.
thanks
UPDATE
var storage;
var yourobj = {
_otherMethod: function() {
// END GOAL OF WHERE I WANT THIS TO BE AVAILABLE
var text = this._requestText();
},
_requestText: function() {
var url = 'http://api.flickr.com/services/feeds/photos_public.gne?format=json';
$.ajax({
type: 'GET',
url: url,
async: false,
dataType: 'jsonp',
success: function(data) {
storage = data;
// logs correctly
console.log(storage);
}
});
}
}
//undefined
console.log(storage);
yourobj._requestText();
//undefined
console.log(storage);

Firstly as noted elsewhere, you need a variable that's in scope, secondly you need to make sure it's not evaluated before the callback is called.
The only way to ensure that is to make the call to _otherMethod inside the success call back method
_otherMethod: function(text) {
//...do what ever you need to do with text
},
_requestText: function() {
var url = 'http://api.flickr.com/services/feeds/photos_public.gne?format=json';
$.ajax({
type: 'GET',
url: url,
async: false,
dataType: 'jsonp',
success: function(data) {
_otherMethod(data);
},
}
});
}
callbacks are asyncronous meaning they are called at some point in time that's not determined by the sequence of code lines.
If you know the code using the returned data is never going to be call before the success call back has executed and you need to hold on to the data you can change the code to
_otherMethod: null, //not strictly needed
_requestText: function() {
self = this;
var url = 'http://api.flickr.com/services/feeds/photos_public.gne?format=json';
$.ajax({
type: 'GET',
url: url,
async: false,
dataType: 'jsonp',
success: function(data) {
self._otherMethod = function(data){
return function(){
//do what you need to with data. Data will be stored
//every execution of _otherMethod will use the same data
console.log(data);
}
}
},
}
});
}

Very simple. You need a storage variable outside of the context of the callback function.
var storage;
var yourobj = {
_otherMethod: function() {
// END GOAL OF WHERE I WANT THIS TO BE AVAILABLE
var text = this._requestText();
},
_requestText: function() {
var url = 'http://api.flickr.com/services/feeds/photos_public.gne?format=json';
$.ajax({
type: 'GET',
url: url,
async: false,
dataType: 'jsonp',
success: function(data) {
storage = data;
}
});
}
}
Alternatively, storage can be a property on the same object.

By adding var before your variable name, you create a local variable in the current scope.
This doesn't work:
var a = 2;
(function() {
var a = 3;
})();
console.log(a); // 2
While this does:
var a = 2;
(function() {
a = 3;
})();
console.log(a); // 3
Since the variable that you're trying to set is in an outer scope, get rid of var when working with it in an inner scope.

might be this way:
_requestText: function() {
var url = 'http://api.flickr.com/services/feeds/photos_public.gne?format=json';
var testvar_1;
$.ajax({
type: 'GET',
url: url,
async: false,
dataType: 'jsonp',
success: function(data) {
console.log(data);
testing(data);
testvar_1 = data;
}
});
// should work here
console.log(testvar_1);
Actually you were creating a new instance of that var there.

jQuery ajax return value [duplicate]

This question already has answers here:
How do I return the response from an asynchronous call?
(41 answers)
Closed 9 years ago.
How can I return the value "pinNumber" from jquery ajax so I can append it outside of the ajax. Here is my code
var x = pinLast + 1;
for(i=x;i<=pinMany;i++) {
var i = x++;
var cardNumber = i.toPrecision(8).split('.').reverse().join('');
var pinNumber = '';
jQuery.ajax({
type: "POST",
url: "data.php",
data: "request_type=generator",
async: false,
success: function(msg){
var pinNumber = msg;
return pinNumber;
//pin number should return
}
});
jQuery('.pin_generated_table').append(cardNumber+' = '+pinNumber+'');
// the variable pinNumber should be able to go here
}
Please ask me if you don't understand.. ^^ thanks

AJAX is asynchronous by default, you cannot return a value from the callback without making a synchronous call, which you almost certainly don't want to do.
You should supply a real callback function to the success: handler, and put your program logic there.

var pinNumber = $.ajax({
type: "POST",
url: "data.php",
data: "request_type=generator",
async: false
}).responseText;
jQuery('.pin_generated_table').append(cardNumber+' = '+pinNumber+' ');

It has to do with variable scope. The local variable pinNumber you create is not accessible outside its wrapping function.
Perhaps declare pinNumber globally or if it'll do the trick, simply stick your .append() inside your success function.

var _successEvent = function(response){
$('.pin_generated_table').append(cardNumber + ' = ' + response);
};
$.ajax({
type: "POST",
url: "data.php",
data: "request_type=generator"
}).done(_successEvent);

You can use this example:
window.variable = 'some data';
This make you variable global and you can access to this from anywhere

Here is the simple solution.
//---------------------------Ajax class ------------------------------//
function AjaxUtil()
{
this.postAjax = function(Data,url,callback)
{
$.ajax({
url: url,
async: true, //must be syncronous request! or not return ajax results
type: 'POST',
data: Data,
dataType: 'json',
success: function(json)
{
callback(json);
}
});
}//--end postAjax
}
//--------------------------------End class--------------------//
var ajaxutil = new AjaxUtil();
function callback(response)
{
alert(response); //response data from ajax call
}
var data={};
data.yourdata = 'anydata';
var url = 'data.php';
ajaxutil.postAJax(data,url,callback);