Pass an array from php to javascript

Question

I'm trying to pass an array from php (on a separate file) side to JavaScript and update HTML table. The array on the php side is a result of MySQL query. Here is what I've done so far:

function updateSensorsTable() {
    $.getJSON("/getTableFromDB.php", function (json) {
     for (i = 0; i < 8;i++ )
         document.getElementById(i).innerHTML = json[i];
    });
}

<?php

include("connect_to_mysql.php");

$result = mysql_query("SELECT value FROM sens" );

while ($row = mysql_fetch_row($result)) {
    $php_array[]=$row[0];
}

echo json_encode($php_array);

?>

Answer 1

Don't forget to set the header :

header('Content-Type: application/json');

When you do "document.getElementById(i)" you try to access on an element witch having a bad ID (integer)... Here is the rule :

ID and NAME tokens must begin with a letter ([A-Za-z]) and may be followed by any number of letters, digits ([0-9]), hyphens ("-"), underscores ("_"), colons (":"), and periods (".").

Answer 2

Here is the complete page

 <script type="text/javascript" > setInterval(updateSensorsTable, 2000); setInterval(updatePower, 1000); function showValue(value) { //show value in html document.getElementById("brightnesValue").innerHTML = value; //Set brightness value to DB id=10 callPage('/setValueToDB.php?value=' + value + '& id=10' + '', document.getElementById('')); } function TurnLedOn() { //TODO: need to set the led state and update the sql server document.getElementById("ledStatus").src = "/LedOn.png"; callPage('/setValueToDB.php?value=1&id=9' + '', document.getElementById('')); } function TurnLedOff() { //TODO: need to set the led state and update the sql server document.getElementById("ledStatus").src = "/LedOff.png"; callPage('/setValueToDB.php?value=0&id=9' + '', document.getElementById('')); } function AjaxCaller() { var xmlhttp = false; try { xmlhttp = new ActiveXObject("Msxml2.XMLHTTP"); } catch (e) { try { xmlhttp = new ActiveXObject("Microsoft.XMLHTTP"); } catch (E) { xmlhttp = false; } } if (!xmlhttp && typeof XMLHttpRequest != 'undefined') { xmlhttp = new XMLHttpRequest(); } return xmlhttp; } function callPage(url, div) { var ajax = AjaxCaller(); ajax.open("GET", url, true); ajax.onreadystatechange = function () { if (ajax.readyState == 4) { if (ajax.status == 200) { div.innerHTML = ajax.responseText; } } } ajax.send(null); } function updateSensorsTable() { for (i = 0; i < 8; i++) { callPage('/getVarFromDB.php?offset=' + i , document.getElementById(i)); } /* $.getJSON("/getTableFromDB.php", function (json) { for (i = 0; i < 8;i++ ) document.getElementById(i).innerHTML = json[i]; }); */ } function updatePower() { callPage('/getVarFromDB.php?offset=' + 10, document.getElementById('powerValue')); } </script>

 <!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8" /> <meta name="viewport" content="width=device-width,height=device-height,initial-scale=1.0"/> <title>SmartLight</title> </head> <body bgcolor="#E6E6FA"> <br></br> <table class="sensorsTable" align="center"> <thead> <tr > <th>Sensor</th> <th>Value</th> </tr> </thead> <tbody> <tr> <td align="left">GPS</td> <td align="center" id="0">0</td> </tr> <tr> <td align="left">Temperature</td> <td align="center" id="1">0</td> </tr> <tr> <td align="left">Pressure</td> <td align="center" id="2">0</td> </tr> <tr> <td align="left">Light</td> <td align="center" id="3">0</td> </tr> <tr> <td align="left">Altitude</td> <td align="center" id="4">0</td> </tr> <tr> <td align="left">Accelerometer</td> <td align="center" id="5">0</td> </tr> <tr> <td align="left">Humidity</td> <td align="center" id="6">0</td> </tr> <tr> <td align="left">Camera</td> <td align="center" id="7">0</td> </tr> </tbody> </table> <br></br> <table class="ledTable" align="center"> <tr> <td align="center"><input type="image" src="/TurnOn.png" id="turnOn" width="60" height="60" onclick='TurnLedOn()'></td> <td align="center"><input type="image" src="/TurnOff.png" id="turnOff" width="60" height="60" onclick='TurnLedOff()'></td> <td align="center"><img src="/LedOn.png" style="width:60px;height:60px" id="ledStatus"></td> </tr> <tr> <td align="center" id="ledOnButton">LED On</td> <td align="center" id="ledOffButton">LED Off</td> <td align="center">LED Status</td> </tr> </table> <div align="center"> Brightness: <input type="range" id="brightnesBar" min="0" max="100" value="0" step="1" onchange="showValue(this.value)" /> <span id="brightnesValue">0</span> <table align="center" class="power"> <tr> <td align="center" id="powerValue">0</td> <td align="left">mW</td> </tr> </table> <div align="center" >LED Power Meter</div> </div>

Pass an array from php to javascript

Question

2 answers

solution1
0 2015-02-10 16:42:16

solution2
0 2015-02-11 07:26:13

Pass an array from php to javascript

Question

2 answers

solution1 0 2015-02-10 16:42:16

solution2 0 2015-02-11 07:26:13

solution1
0 2015-02-10 16:42:16

solution2
0 2015-02-11 07:26:13