Develop Reference

JavaScript: How to get http response as a result of click

I'm trying to get response of GET request, that starts after document.getElementById('btnPdf').click();
I'm using Selenium Webdriver as JavaScriptExecutor.
My question is similar to this How do I capture response of form.submit but I don't know exact url and would prefer to use pure JS without AJAX (if it's possible).

function get
Response() {
var send1='senddata'; // this is a var to send
var send2='senddata2'; // this is another var to send
var xhr = new XMLHttpRequest();
xhr.open('POST', 'myGetPageName',true);
xhr.setRequestHeader('Content-Type', 'text/plain');
xhr.onload = function() {
if (xhr.status === 200) {
var myResponse = xhr.responseText;
alert(myResponse);
}
};
xhr.send('myvar1=' + send1 + '&myvar2=' + send2)
}

xmlhttp.open multiple XML files

How would I go about fetching multiple XML files? I tried creating an array but that only opens the last file, and as I understand it xmlhttp.open is supposed to cancel any previous send. I tried modifying this which was the closest thing I could find, but my JavaScript knowledge is a bit to limited to adapt it.
This is the basic code I'm using to get one XML file.
if (window.XMLHttpRequest)
{ xmlhttp=new XMLHttpRequest();
}
xmlhttp.open("GET","myfile.xml",false);
xmlhttp.send();
xmlDoc=xmlhttp.responseXML;
var x=xmlDoc.getElementsByTagName("TAGNAME");
for (i=0;i<x.length;i++)
{ // Further parsing
}
Also is it possible to then display which file the parsed content comes from in my loop?

try this:
var arr = ["file1.xml", "file2.xml"],
cnt = 0, xhr = new XMLHttpRequest(), method = "GET";
function formatXml(file, xmlDoc) {
var x=xmlDoc.getElementsByTagName("TAGNAME");
console.log(file,x);
}
function getXml() {
xhr.open(method, arr[cnt], true);
xhr.onreadystatechange = function() {
if (xhr.readyState === XMLHttpRequest.DONE && xhr.status === 200) {
formatXml(arr[cnt], xhr.responseText);
cnt++;
if (cnt < arr.length) getXml(); // call again
}
};
xhr.send();
}
getXml(); // start it

What is the vanilla JS version of Jquery's $.getJSON

I need to build a project to get into a JS bootcamp I am applying for. They tell me I may only use vanilla JS, specifically that frameworks and Jquery are not permitted. Up to this point when I wanted to retrieve a JSON file from an api I would say
$.getJSON(url, functionToPassJsonFileTo)
for JSON calls and
$.getJSON(url + "&callback?", functionToPassJsonPFileTo)
for JSONP calls. I just started programming this month so please bear in mind I don't know the difference between JSON or JSONP or how they relate to this thing called ajax. Please explain how I would get what the 2 lines above achieve in Vanilla Javascript. Thank you.
So to clarify,
function jsonp(uri){
return new Promise(function(resolve, reject){
var id = '_' + Math.round(10000 * Math.random())
var callbackName = 'jsonp_callback_' + id
window[callbackName] = function(data){
delete window[callbackName]
var ele = document.getElementById(id)
ele.parentNode.removeChild(ele)
resolve(data)
}
var src = uri + '&callback=' + callbackName
var script = document.createElement('script')
script.src = src
script.id = id
script.addEventListener('error', reject)
(document.getElementsByTagName('head')[0] || document.body || document.documentElement).appendChild(script)
})
}
would be the JSONP equivalent?

Here is the Vanilla JS version for $.getJSON :
var request = new XMLHttpRequest();
request.open('GET', '/my/url', true);
request.onload = function() {
if (request.status >= 200 && request.status < 400) {
// Success!
var data = JSON.parse(request.responseText);
} else {
// We reached our target server, but it returned an error
}
};
request.onerror = function() {
// There was a connection error of some sort
};
request.send();
Ref: http://youmightnotneedjquery.com/
For JSONP SO already has the answer here
With $.getJSON you can load JSON-encoded data from the server using
a GET HTTP request.

ES6 has Fetch API which provides a global fetch() method that provides an easy, logical way to fetch resources asynchronously across the network.
It is easier than XMLHttpRequest.
fetch(url) // Call the fetch function passing the url of the API as a parameter
.then(res => res.json())
.then(function (res) {
console.log(res)
// Your code for handling the data you get from the API
})
.catch(function() {
// This is where you run code if the server returns any errors
});

Here is a vanilla JS version of Ajax
var $ajax = (function(){
var that = {};
that.send = function(url, options) {
var on_success = options.onSuccess || function(){},
on_error = options.onError || function(){},
on_timeout = options.onTimeout || function(){},
timeout = options.timeout || 10000; // ms
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
//console.log('responseText:' + xmlhttp.responseText);
try {
var data = JSON.parse(xmlhttp.responseText);
} catch(err) {
console.log(err.message + " in " + xmlhttp.responseText);
return;
}
on_success(data);
}else{
if(xmlhttp.readyState == 4){
on_error();
}
}
};
xmlhttp.timeout = timeout;
xmlhttp.ontimeout = function () {
on_timeout();
}
xmlhttp.open("GET", url, true);
xmlhttp.send();
}
return that;
})();
Example:
$ajax.send("someUrl.com", {
onSuccess: function(data){
console.log("success",data);
},
onError: function(){
console.log("Error");
},
onTimeout: function(){
console.log("Timeout");
},
timeout: 10000
});

I appreciate the vanilla js equivalent of a $.getJSON above
but I come to exactly the same point. I actually was trying of getting rid of jquery which I do not master in any way .
What I'm finally strugglin with in BOTH cases is the async nature of the JSON request.
What I'm trying to achieve is to extract a variable from the async call
function shorten(url){
var request = new XMLHttpRequest();
bitly="http://api.bitly.com/v3/shorten?&apiKey=mykey&login=mylogin&longURL=";
request.open('GET', bitly+url, true);
request.onload = function() {
if (request.status >= 200 && request.status < 400) {
var data = JSON.parse(request.responseText).data.url;
alert ("1:"+data); //alerts fine from within
// return data is helpless
}
};
request.onerror = function() {
// There was a connection error of some sort
return url;
};
request.send();
}
now that the function is defined & works a treat
shorten("anyvalidURL"); // alerts fine from within "1: [bit.ly url]"
but how do I assign the data value (from async call) to be able to use it in my javascript after the function was called
like e.g
document.write("My tiny is : "+data);

AJAX, pass additional variable to callback and store XMLHTTLRequest.response to variable

I am trying to read a local file on the server with a standard function loadDoc(url, cfunc), then
1) search for a particular string in the file (getLine());
2) if possible, store that line to a variable.
For point 1 I pass a string to the callback.
2) Getting the response is problematic because XMLHTTPRequest is asynchronous. At this moment the error is:
"ReferenceError: xhttp is not defined"
function main(){
var url="data.txt"
var str="1,0,"; //just an example
var myCallBackWithVar = function(){
getLine(str);
};
loadDoc(url, myCallBackWithVar);
//Can I get the line here somehow?
}
function loadDoc(url, cfunc) {
var xhttp=new XMLHttpRequest();
xhttp.onreadystatechange = function() {
if (xhttp.readyState == 4 && xhttp.status == 200) {
cfunc(xhttp);
}
}
xhttp.overrideMimeType('text/plain');
xhttp.open("GET", url, true);
xhttp.send();
}
//Find string with the desired data in txt file
function getLine(str) {
var data=xhttp.responseText;
//Find the line from the txt file
var start=data.indexOf(str);
var end=data.indexOf(";",start);
var line=data.substring(start,end);
return line;
}
data.txt is something like this:
some data here
0,0,9;
1,0,10;
1,1,11;
I have already tried to pass the XMLHTTPRequest objetct getLine(xhttp,str). How to solve points 1 and 2? I'd rather keep it jQuery free for the moment. Thanks

Can I get the line here somehow?
I don't think that's a good idea. You can't be sure that your app will work correctly. XHR is a async function and you should use async architecture.
Here the example how this functionality can be done.
var text; // define global variable
var str = "1,0,"; //just an example
function main(){
var url = "data.txt";
var cb = function (data){
text = getLine(data);
// you can use text var here
// or in anyewhere in your code
}
loadDoc(url, cb);
}
function loadDoc(url, cb) {
var xhr = new XMLHttpRequest();
xhr.onreadystatechange = function() {
if (xhr.readyState == 4 && xhr.status == 200) {
cb(xhr.responseText);
}
}
xhr.overrideMimeType('text/plain');
xhr.open("GET", url, true);
xhr.send();
}
//Find string with the desired data in txt file
function getLine(data) {
if(data) {
//Find the line from the txt file
var start = data.indexOf(str);
var end = data.indexOf(";", start);
var line = data.substring(start, end);
return line;
}
}

On complete, you don't need to pass the whole xhttp variable through too the callback function. When you do this:
function getLine(str) {
var data=xhttp.responseText;
xhttp is already out of scope. To fix this, the parameter name would also have to be xhttp.
A better way would be to do :
cfunc(xhttp.responseText);
and then
var data=str
This way, you are passing only what you need as an argument.

Reading CSV file in to an array using javascript

I'm trying to do something fairly simple I think but I'm missing something. I've very new to Javascript. I'm trying to read a CSV file in to an array (in my code below I'm simply trying to output the data to an alert box). I keep getting an error "access denied."
function readTextFile(file) {
var rawFile = new XMLHttpRequest();
rawFile.open("GET", file, true);
rawFile.onreadystatechange = function () {
if(rawFile.readyState === 4) {
if(rawFile.status === 200 || rawFile.status == 0) {
var allText = rawFile.responseText;
alert(allText);
}
}
}
rawFile.send(null);
}
I suspect there is an issue with where I have the csv file located? Due to restrictions with our CMS I can only reference the file like this www.example.com/csvfile.csv.
Any help would be greatly appreciated.

Here is sample code for reading csv file into array
var request = new XMLHttpRequest();
request.open("GET", url, false);
request.send(null);
var csvData = new Array();
var jsonObject = request.responseText.split(/\r?\n|\r/);
for (var i = 0; i < jsonObject.length; i++) {
csvData.push(jsonObject[i].split(','));
}
// Retrived data from csv file content
console.log(csvData);
Here is the working fiddle example: http://jsfiddle.net/BdCnm/450/

Give this link a try and check his source code on Github, he lays it out in a pretty concise way.
https://github.com/MounirMesselmeni/html-fileapi