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JavaScript Saving data from an ajax request

Challenge:
While on URL1(random wikipedia page), make an ajax request to URL2(100 most common words wikipedia page), format a list out of the returned data to be used later.
I have to run this from the console while on "URL1"
example:
Navigate to URL1
Open Console
paste code
hit enter
So far I have been able to grab the entire html source while on URL1 with the following:
$.ajax({
url: 'https://en.wikipedia.org/wiki/Most_common_words_in_English',
type: 'GET',
dataType: 'html',
success: function (response) {
console.log(response); // works as expected (returns all html)
}
});
I can see in the console the entire HTML source -- I then went to URL2 to figure out how to grab and format what I needed, which I was able to do with:
var array = $.map($('.wikitable tr'),function(val,i){
var obj = {};
obj[$(val).find('td:first').text()] = $(val).find('td:last').text();
return obj;
});
console.log(JSON.stringify(array));
Now this is where my issue is -- combining the two
$.ajax({
url:'https://en.wikipedia.org/wiki/Most_common_words_in_English',
type:'GET',
dataType:'html',
success: function(data){
// returns correct table data from URL2 while on URL2 -- issue while running from URL1
var array = $.map($('.wikitable tr'),function(val,i){
var obj = {};
obj[$(val).find('td:first').text()] = $(val).find('td:last').text();
return obj;
});
console.log(JSON.stringify(array));
};
});
Im guessing this is due to the HTML I want to map is now a string, and my array is looking for HTML elements on the current page which it of course would not find.
Thanks

Simple fix here! You're exactly right, it's not parsing the html you return, so just tell jQuery to convert it into an object it can use $(data) and use that to find what you need.
In essence, your 'document' now becomes $(data) which you will use as the source of all your queries.
$.ajax({
url: 'https://en.wikipedia.org/wiki/Most_common_words_in_English',
type: 'GET',
dataType: 'html',
success: function(data) {
var myVar = data;
Names = $.map($(myVar).find('.wikitable tr'), function(el, index) {
return $(el).find('td:last').text()
});
console.log(Names);
}
});

Sending large javascript array to Web API

I am struggling with this issue for 2 days...
I have a JavaScript array (20,000K rows and 41 columns). It was originally received in javaScript through an ajax call as shown below,
var dataArray = [];
var dataRequest = {};
dataRequest.SearchCondition = 'some value';
$.ajax({
type: "POST",
url: "api/GetData/ProcessRequest",
dataType: 'json',
cache: false,
async: true,
crossDomain: false,
data: dataRequest ,
success: function (response) {
dataArray = response;
},
error: function (xhr, textStatus, errorThrown) {
dataArray = null;
}
});
In the application, the user will verify the data and send it back to Web API method.
I am trying to send the same data back (dataArray) to web api method but, it fails. Please see the code below,
Option 1: (failed - the request did not hit web api method)
var dataArrayJsonStr = JSON.stringify(dataArray);
$.ajax({
type: "POST",
url: "api/SendData/ProcessRequest",
dataType: 'json',
data: {'dataValue':dataArrayJsonStr },
success: function (response) {
alert('success');
},
error: function (xhr, textStatus, errorThrown) {
alert(errorThrown)
}
});
In IE 8, I am getting 'out of memory' exception popup. (most of our application users still have IE 8)
In Chrome, it crashes.
Option 2 tried: (don't know how to read the value)
I tried to send the same value to web api through XmllHttpRequest
var dataArrayJsonStr = JSON.stringify(dataArr);
var xmlRequest;
if (window.XMLHttpRequest) {
xmlRequest = new XMLHttpRequest();
}
xmlRequest.open("POST", "api/SendData/ProcessRequest", false);
xmlRequest.setRequestHeader('Content-Type', 'application/text');
xmlRequest.send("dataValue=" + dataArrayJsonStr);
Using Chrome, I am able to post the data successfully to Web API, I am seeing the content-length as '128180309'. But, I don't see the values. How do i get the values in Web API?
Please suggest me how to send large data back to web api from javascript.
Thanks,
Vim

I think you create overhead, maybe I wrong, you can edit me.
Did you really need send back all datas back or you just need send modified data?
Because in real life hard to imagine that user will review 20.000 of rows.
Good example is ExtJS stores, you can see example here
Key thing of stores that they send back to the server only modified or deleted data, it save browser, network and server resources.

Try to add more memory for API or more time excecution, also you can try return data in more small parts. Defining the number of parts to send.

Did you try to send the data by chunks?
I mean, you need to split it in small pieces and perform multiple number of requests.
For example, it can be like:
--HELLO SERVER. STARTING TRANSMITION FOR DATA SET #177151--
PIECE 1/13
PIECE 2/13
...
PIECE 13/13
--BUE SERVER--
So, it will take some time, but you can send any amounts of data without memory problems. If you're struggling with it for 2 days, I think you got some time to code it :)
UPD1: Client code example.
Here's an example of client code. This is a simple chunking algorithm.
Have to say I didn't test it, because it would take a lot of time to represent your situation.
So, you should read it and get the point.
You have a simple function, that takes you whole data set and callbacks for each response (to update your progress bar, e.g.), for successful finish and for error.
Hope, it will help you to make some problems.
Also, I can help you to build architecture on the server-side, but I need to know what technologies do you use.
function sendData(data, onEach, onFinish, onError) {
var CHUNK_SIZE = 1000;
var isFailed = false;
var chunkNum = 0;
var chunk, chunkStart, chunkEnd;
while(data.length + CHUNK_SIZE > chunkNum * CHUNK_SIZE) {
if(isFailed) {
return;
}
chunkStart = chunkNum * CHUNK_SIZE;
chunkEnd = chunkStart + CHUNK_SIZE + 1;
chunk = {
num: chunkNum,
data: data.slice(chunkStart, chunkEnd)
};
ajaxCall(chunk);
chunkNum++;
}
function ajaxCall(data) {
$.ajax({
type: "POST",
url: "api/GetData/ProcessRequest",
dataType: 'json',
async: true,
data: dataRequest ,
success: function (response) {
onEach(data, response);
},
error: function (xhr, textStatus, errorThrown) {
isFailed = true;
onError(arguments);
}
});
}
}

AJAX call using IIFE? Can't seem to get .done to work the same as a regular function

I currently have an AJAX call out to a PHP file that works, that is the following:
//Load map from database
function getMap(){
return $.ajax({
url: "getMap.php",
type: "POST",
dataType: 'JSON',
});
};
getMap().done(function(r) {
if (r) {
loadedMap(JSON.parse(r.mapArray), JSON.parse(r.mapProperties)); //call loadedMap(r) if loading a map from DB
} else {
console.log("No data");
}
}).fail(function(x) {
console.log("error");
});
That works within a single javascript file that successfully passes r.mapArray and r.mapProperties to my main loadedMap function.
I'm trying to learn about the IIFE Javascript Module model, and split my work up into separate files.
So, I currently have main.js:
(function() {
// let's get our map
var gameMap = mapGen.getMap().done();
console.log(gameMap);
})();
and mapGen.js:
var mapGen = function() {
return {
getMap: function() {
return $.ajax({
url: "getMap.php",
type: "POST",
dataType: 'JSON',
});
}
};
}()
If I console.log(gameMap), I see the responseText JSON object with my data. I just can't seem to access it. console.log(gameMap.responseText) is undefined. as is gameMap.responseJSON (though I see both of them in the console).

Looking the code over it looks as the the separation of the files was not the issue and that looks to be implemented correctly. The issue is with how you are handling the AJAX request. The function mapGen.getMap() actually returns a jqXHR Object as opposed to the response that you are trying to access.
Just as you had in your previous file, you will need handle the response of your request.
(function() {
// let's get our map request
var gameMap = mapGen.getMap();
gameMap.done(function(r){ ... }).
fail(function(x){ ... });
})();
You will be able to access the response data you are looking for within the done() function.

Setting string in javascript function in ASP.NET MVC give NullReferenceException

Inside my MVC view I have javascript that is executed by a button click. I'm trying to set a string to a random set of characters which I can get to work fine but when I try and set that string to 'randomchars' string inside the javascript I get a NullReferenceException when I try and run the view.
Below is the code snippet, the CreateRString is where the model parameter (RString) is set to the random string.
<script type="text/javascript">
function showAndroidToast(toast) {
var url = '#Url.Action("CreateRString", "Functions")';
$.ajax({ url: url, success: function (response) { window.location.href = response.Url; }, type: 'POST', dataType: 'json' });
var randomchars = '#(Model.RString)';
}
</script>
Is the syntax correct? I'm not too sure why it's getting the NULL.

The javascript is executed after the page been delivered to the client (i.e. web browser). Your razor code here is executed on the server before the page is sent to the client. Therefore, the ajax method will execute after you try to access Model.RString
To fix this you can either call CreateRString on the server, or you can set randomchars by using the response in the success callback.
To explain option 2 a bit further. You could do something like this:
//Action Method that returns data which includes your random chars
public JsonResult CreateRString()
{
var myRandomChars = "ABCDEF";
return new JsonResult() { Data = new { RandomChars = myRandomChars } };
}
//The ajax request will receive json created in the CreateRString method which
//contains the RandomChars
$.ajax({ url: url, success: function (response) {
var randomchars = response.Data.RandomChars;
window.location.href = response.Url;
}, type: 'POST', dataType: 'json' });
More specifically, the razor calls #Url.Action("CreateRString", "Functions") and #(Model.RString) execute first on the server.
Then showAndroidToast executes in the client's browser when you call it.

returning part of a json file as a variable in jquery

I am attempting to create a glossary tooltip for a website that finds keywords from a json file that is being created by sitecore. I need to get the "Text:" parts from the json file and make then a variable in my jquery so they are the keywords that are found and wrapped with the appropriate tags. I had it working to the point where i could get console to log that there were 2 entries in my json file but that's it.
Here is my sample json code:
[{"Id":"ef339eaa-78e1-4f9e-911e- 096a1920f0b6","Name":"Glossary","DisplayName":"Glossary","TemplateId":"b27d2588-3d02-4f5f-8064-2ee3b7b8eb39","TemplateName":"Glossary","Url":"/Global-Content/Glossary/Glossary","Version":1,"Created":"\/Date(1343987220000)\/","CreatedBy":"sitecore\\rgoodman","Revision":"ae8b3ae0-d0ca-4c4a-9f27-a542a31ab233","Updated":"\/Date(1348137810133)\/","UpdatedBy":"sitecore\\admin","Text":"Glossary","Content":"A bit of test content for the glossary"},{"Id":"3fa51ad4-cfb6-4ff1-a9b5-5276914b2c23","Name":"Abraham","DisplayName":"Abraham","TemplateId":"b27d2588-3d02-4f5f-8064-2ee3b7b8eb39","TemplateName":"Glossary","Url":"/Global-Content/Glossary/A/Abraham","Version":1,"Created":"\/Date(1348148640000)\/","CreatedBy":"sitecore\\admin","Revision":"231284ec-9fb9-4502-ad79-a5806479ecba","Updated":"\/Date(1348148779656)\/","UpdatedBy":"sitecore\\admin","Text":"Abraham","Content":"This is a lincoln person"}]
But I suppose this is not of any use as it is just the "Text:" part i am looking to return.
Here is my jquery:
function getData(url) {
var data;
$.ajax({
async: false,
url: '/_assets/js/glossary.json',
dataType: 'json',
success: function(data.Text){
data.Text = response;
}
return(response);
});
}
function HighlightKeywords(keywords)
{
var el = $("body");
$(keywords).each(function()
{
var pattern = new RegExp("(" +this+ ")", ["gi"]);
var rs = "<mark href='#' class='tooltip'>$1</mark>";
el.html(el.html().replace(pattern, rs));
});
}
HighlightKeywords(data.Text);
Essentially i need to return the "Text:" bit of json where data is on the HighlightKerywords function. Where am i going wrong?
Any help would be much appreciated. Thanks

Your function is not syntactically formatted properly. Your return must go inside of the success function in the synchronous example, and not randomly placed in the ajax object..
function getData() {
$.ajax({
async: false,
url: '/_assets/js/glossary.json',
dataType: 'json',
success: function(data){
//HighlightKeywords(data.Text);
//or
return(data.Text);
}
});
}

Ajax is Asynchronous communication, you can't insert its response into a global variable and expect to be able to work with it.
You need to do all the work on the data.text in the success function.
success: function(response){
HighlightKeywords(response.Text);
}