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I am passing an array of string from the file indexOnLoad.php. After getting this with the help XMLHttpRequest() in JavaScript when I return this array I get the variable as 'undefined'.

The HTML code is:

    <!DOCTYPE html>
<html>

<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="NavBar.css">
    <link rel="stylesheet" href="indexCSS.css">
    <script src="indexJS.js" charset="utf-8"></script>
    <script type="text/javascript">
        var arrayString;
    </script>
    <title>Find your Bus</title>
</head>`enter code here`

<body bgcolor=#81D4FA onkeypress="test();" onload="arrayString = indexOnLoad();console.log('arrayString ');console.log(arrayString);">
    <ul class="NavBar">
        <li class="NavBarList" id="Home">
            <a href="#" style="text-decoration: none; color: white;">
                Home
            </a>
            <div class="NavBarListContent" id="homeContent">
                <a href="#">About</a>
                <a href="#">Developers</a>
                <a href="#">Suggestions Box</a>
            </div>
        </li>
        <div style="float: right;">
            <li class="NavBarList">
                Administrator
            </li>
        </div>
    </ul>
    <div class="filler1">

    </div>
    <div class="SearchBox">
        <input type="text" id="textBoxSearchQuery" placeholder="Search for Anywhere..." list="suggestions"><datalist id="suggestions">
            <option value="Manan">Manan</option>
            <option value="Anant">Anant</option>
        </datalist><img src="search-89.png" name="buttonSearch" value="Search" id="buttonSearch">
    </div>

</body>

</html>

Please take a look on the body tag and the script containing main problem code. JavaScript file, which is named as "indexJS.js" is:

        function indexOnLoad() {
    var xhttp = new XMLHttpRequest();
    xhttp.onreadystatechange = function() {
        if (this.readyState == 4 && this.status == 200) {
            var obj = JSON.parse(this.responseText);
            return obj;
        }
    };
    xhttp.open("GET", "indexOnLoad.php", true);
    xhttp.send();
}

The PHP file, which is named as "indexOnLoad.php" is:

<?php

$array = array("1","2","3");

$json = json_encode($array);
echo $json;
?>

the results after this in browser

Bharata
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Manan Trimbakey
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  • `var arrayString =""; window.onload=function() { var xhttp = new XMLHttpRequest(); xhttp.onreadystatechange = function() { if (this.readyState == 4 && this.status == 200) { arrayString = JSON.parse(this.responseText); console.log(arrayString); /* process here */ } }; xhttp.open("GET", "indexOnLoad.php", true); xhttp.send(); }} ` – mplungjan Jan 15 '18 at 07:22
  • the problem is when I access arrayString variable outside of the responseText block i always get undefined – Manan Trimbakey Jan 15 '18 at 07:34
  • Read the duplicate. The A in AJAX stands for "Asynchronous" which means the value is available AFTER the successful return from the call and nowhere else. Put the call to the processing inside the onreadystatechange function – mplungjan Jan 15 '18 at 07:35
  • Thanks... for all the efforts – Manan Trimbakey Jan 15 '18 at 07:39

0 Answers0