Develop Reference

API not responding

The app that I'm working on does not respond with the API address. I only get the ajax responding, but not the weather api that I'm trying to call.
I've tried everything that I could think of with my current knowledge.
let search = document.getElementById("search-bar");
let temp = document.getElementById("temperature");
let input = document.getElementById("input");
let city = document.getElementById("city");
const key = "";
input.addEventListener("keyup", enter);
function enter(event) {
if (event.key==="Enter") {
details();
}
}
function details() {
if (searchInput.value === ""){
} else {
let searchLink = "https://api.openweathermap.org/data/2.5/weather?q={}" + searchInput.value + "&appid=" + key;
httpRequestAsync(searchLink, talk)
}
}
function talk(talking){
let jsonObject = JSON.parse(talking);
city.innerHTML = jsonOject.name;
temp.innerHTML = parseInt(parseInt(jsonObject.main.temp - 273) + "°");
}
function httpRequestAsync(url,callback){
var httpRequest=new XMLHttpRequest();
httpRequest.onreadystatechange = () => {
if (httpRequest.readyState == 4 && httpRequest.status == 200)
callback(httpRequest.responseText);
}
request.open("GET", url, true); // true for asynchronous
request.send();
}
The expected outcome should be the weather api being called and displayed information in the console.

Try replacing last function with this:
function httpRequestAsync(url,callback){
var httpRequest=new XMLHttpRequest();
httpRequest.onreadystatechange = () => {
if (httpRequest.readyState == 4 && httpRequest.status == 200)
callback(httpRequest.responseText);
}
httpRequest.open("GET", url, true); // true for asynchronous
httpRequest.send();
}
I just corrected variable naming

JavaScript: Variables not working outside function?

Why cannot I call variables that I have defined inside a function? This is my code...
var username;
var rank;
var steamid;
var avatar;
var xhr = new XMLHttpRequest();
xhr.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
if (this.responseText == "null") {
} else {
var infoArr = JSON.parse(this.responseText);
var username = infoArr.username;
var rank = infoArr.rank;
var steamid = infoArr.steamid;
var avatar = infoArr.avatar;
testIt();
}
}
};
xhr.open("GET", "../getInfo.php", true);
xhr.send();
function testIt() {
alert(username);
}
Function testIt() is returning: undefined
What my code does is to get info from a JSON encoded page and make variables.

If you want to use the variables outside of the function, they need to be defined outside of the function.
var username, rank, steamid, avatar, infoArr, username, rank, steamid, avatar;
var xhr = new XMLHttpRequest();
xhr.onreadystatechange = function() {
if (this.readyState == 4 && this.status == 200) {
if (this.responseText == "null") {
} else {
infoArr = JSON.parse(this.responseText);
username = infoArr.username;
rank = infoArr.rank;
steamid = infoArr.steamid;
avatar = infoArr.avatar;
testIt();
}
}
};
xhr.open("GET", "../getInfo.php", true);
xhr.send();
function testIt() {
alert(username);
}

AJAX does not return object

I am using AJAX GET to get a local JSON file and it does that, but once i try to return it says undefined.
ScoreHandler = function () {
this.getScores = function() {
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function () {
if (this.readyState == 4 && this.status == 200) {
var data = JSON.parse(this.responseText);
//This logs object
console.log(data);
return data;
}
};
xmlhttp.open("GET", "JSON/Scores.json", true);
xmlhttp.send();
};
};
HighScores = function (scoreHandler) {
var scoreHandler = scoreHandler;
var scores = this.scoreHandler.getScores();
//This logs undefined
console.log(scores);
}

Just implement a callback for response, something like this
ScoreHandler = function () {
this.getScores = function(callback) {
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function () {
if (this.readyState == 4 && this.status == 200) {
var data = JSON.parse(this.responseText);
//This logs object
console.log(data);
if(typeof callback === 'function')
callback(data);
//return data;
}
};
xmlhttp.open("GET", "JSON/Scores.json", true);
xmlhttp.send();
};
};
HighScores = function (scoreHandler) {
var scoreHandler = scoreHandler; //why this line use it directly
var scores = this.scoreHandler.getScores(function(data){
console.log("response", data); //you can see the data here
});
//This logs undefined
console.log(scores);
}

Loop Calling Function in Native Ajax

Here's my native ajax code:
function script_grabbed(str) {
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
document.getElementById("numvalue").value = xmlhttp.responseText;
var result = document.getElementById("numvalue").value;
if (typeof result !== 'undefined'){
alert('Data Found:' + result);
//start: new request data for #valdata
xmlhttp.open("POST", "inc.php?q="+str, true);
document.getElementById("valdata").value = xmlhttp.responseText;
xmlhttp.send(null);
var dataval = document.getElementById("valdata").value;
if (typeof dataval !== 'undefined'){
alert('Data Bound:' + dataval);
//continue to call maps
script_dkill()
}
//end: new request data for #valdata
}
}
}
xmlhttp.open("POST", "inc_num.php?q="+str, true);
xmlhttp.send(null);
}
From the code, let me explain that:
I want to get data/value from result and dataval. After I get the data, I execute script_dkill() function.
However, It creates loop and never get to script_dkill.
So, the question is: How to get to script_dkill and execute it?
For example:
The script_dkill() has content as follow:
function script_dkill(){
alert('Hallo, you call me!');
}
Any help, please...

You need to use a different XMLHttpRequest object for the second request, since you are using the same object it will call the same onreadystatechange event again and again
function script_grabbed(str) {
var xmlhttp = new XMLHttpRequest();
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200) {
document.getElementById("numvalue").value = xmlhttp.responseText;
var result = document.getElementById("numvalue").value;
if (typeof result !== 'undefined') {
alert('Data Found:' + result);
//start: new request data for #valdata
var xmlhttp2 = new XMLHttpRequest();
xmlhttp2.onreadystatechange = function() {
if (xmlhttp2.readyState == 4 && xmlhttp2.status == 200) {
document.getElementById("valdata").value = xmlhttp2.responseText;
var dataval = document.getElementById("valdata").value;
if (typeof dataval !== 'undefined') {
alert('Data Bound:' + dataval);
//continue to call maps
script_dkill()
}
}
}
xmlhttp2.open("POST", "inc.php?q=" + str, true);
xmlhttp2.send(null);
//end: new request data for #valdata
}
}
}
xmlhttp.open("POST", "inc_num.php?q=" + str, true);
xmlhttp.send(null);
}

Browser freeze when calling an ajax post / get methods

I have two ajax functions which freeze the window whenever they are called.
Is there a way to prevent such behaviour ? (Pure javascript).
Here's the two functions:
function fetch_json_data(a)
{
if (window.XMLHttpRequest) { xmlhttp = new XMLHttpRequest() }
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200)
{
var json_response = JSON.parse(xmlhttp.responseText);
for (var key in json_response)
{
if(json_response[key] != null && json_response[key].length > 0)
{
var e = document.getElementById(key+".div");
e.innerHTML = "<pre>"+json_response[key]+"</pre>";
var e = document.getElementById(key);
e.setAttribute("class", "active");
e.parentNode.parentNode.previousElementSibling.setAttribute("class", "active");
results_status[key] = true;
if (key.match("sh"))
{
quick_info.children[2].innerHTML += key + ", ";
}
quick_info.setAttribute("class", "show-data");
close_alert();
}
}
}
}
xmlhttp.open("POST","ajax.php", false);
xmlhttp.setRequestHeader("Content-type","application/x-www-form-urlencoded");
xmlhttp.send(a);
}
function number 2:
function fetch_data(a, b)
{
if (window.XMLHttpRequest)
{
xmlhttp = new XMLHttpRequest();
}
xmlhttp.onreadystatechange = function() {
if (xmlhttp.readyState == 4 && xmlhttp.status == 200)
{
if (last_fetched_element != null) { last_fetched_element.removeAttribute("class") }
last_fetched_element = document.getElementById(b.id+".div");
var t = last_fetched_element;
var response = xmlhttp.responseText;
if (xmlhttp.responseText.length == 0) response = "No Data";
t.innerHTML = "<pre>" + response + "</pre>";
t.setAttribute("class", "show-data");
document.getElementById(b.id).setAttribute("class", "active");
close_alert();
results_status[b.id] = true;
}
}
xmlhttp.open("POST","ajax.php", false);
xmlhttp.setRequestHeader("Content-type","application/x-www-form-urlencoded");
xmlhttp.send(a); // "fname=Henry&lname=Ford"
}
I can't tell why this is happening. the response arrive rather quickly, but still,
I would be nice to avoid that freeze.

it is because you are using a synchronous call, try asynchronous
set the third parameter of open to true

The XMLHttpRequest.open() function. The third parameter sets Async or Normal. With Async set to true the browser won't freeze. With normal, the browser will freeze and wait for everything to be loaded. So change your lines.
xmlhttp.open("POST","ajax.php", false);
To:
xmlhttp.open("POST","ajax.php", true);