Store value in DB with PHP - Ajax call from JavaScript

Question

i want to store a value in a database with PHP. I call a PHP-function with AJAX.

I check on document.ready() if the website was called with a parameter called temperature:

$(document).ready(function(){
 var data = 5; //gup('temperature', location.href);
 if(data != undefined){
 var sendData = 'func=storeValue&value=' + data + '&datetime=' + getDateTime();
 $.ajax({
 data: sendData,
 type: "POST",
 url: "FunctionManager.php",
 success: function(data){
 alert("Data Saved " + data);
 },
 error: function(xhr){
 alert(xhr.responseText);
 }
 })
 }
}

I use a the php file "FunctionManager" to call the according function which i determine with the passed parameters. So i pass dataand datetime. My FunctionManager looks like this:

 <?php
 include "$_SERVER[DOCUMENT_ROOT]/SQLCommunication.php";
 header('Content-Type: application/json');
 if(!isset($_GET['func']) && empty($_GET['func'])){
 exit();
 }
 if($_POST['func'] === "readValue"){
 echo readValue();
 }elseif($_POST['func'] === "storeValue"){
 echo storeValue($_POST["value"], $_POST["datetime"]);
 }
 ?>

So as you can see i first check which function is called and then call the function itself with parameters. I know that this works because i have a new row in my database after calling the website with a parameter. But the fields datetime and value are always zero. My storeValue- function is located in SQLCommunication.phpand looks like this:

function storeValue($val, $datetime){ 
 $conn = establishConnection();
 if($conn->connect_error){
 die("Connection failed: ". $conn->connect_error);
 }
 //$datetime = date_default_timezone_get();
 //$datetime = '2016-01-04 00:18:00';
 $sql = "INSERT INTO tempvalues (datetime, value) VALUES ('$datetime', '$val')";
 $conn->query($sql);
 $conn->close();
}

This is the function i use to read the temperature parameter:

function gup( name, url ) {
 if (!url) url = location.href;
 name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");
 var regexS = "[\\?&]"+name+"=([^&#]*)";
 var regex = new RegExp( regexS );
 var results = regex.exec( url ).toString();
 return results == null ? null : results[1];
}

Do you have any ideas which mistake i made? Thanks

• Fakhruddin Ujjainwala: what is your database datatype for datetime?
• binaryBigInt: It is datetime. And the datatpye of value is INT
• Garytje: i believe that when you do a jquery post, you can not send any get variables..
• binaryBigInt: So should i change it to GET? No, it also does not work.

Answer 1

The jquery code must be like this. If you look at your browser console, you may see some errors. The jquery should be like this:

var date = new Date();
var year = date.getFullYear();
var month = date.getMonth() + 1;
var day = date.getDate();
var hours = date.getHours();
var minutes = date.getMinutes();
var seconds = date.getSeconds();
newdate = year + "-" + month + "-" + day + " " + hours + ":" + minutes + ":" + seconds;
$(document).ready(function(){
 var storeValue = 'storeValue';
 var data = gup('temperature', location.href); 
 if(data != undefined){
 yourData = 'func='+storeValue+'&value='+data+'&newdate='+newdate;
 $.ajax({
 data: yourData,
 type: "POST",
 url: "FunctionManager.php,
 success: function(data){
 alert("Data Saved " + data);
 },
 error: function(xhr){
 alert(xhr.responseText);
 }
 });
 }
});

In Functionmanager.php

 print_r($_POST);
 include "$_SERVER[DOCUMENT_ROOT]/SQLCommunication.php";
 header('Content-Type: application/json');
 if(!isset($_POST['func']) || empty($_POST['func'])){
 exit();
 }else{
 $func = isset($_POST['func'])? $_POST['func']: 'storeValue';
 $val = isset($_POST['value'])? $_POST['value']:'';
 $datetime = isset($_POST['newdate'])? $_POST['newdate']:'';
 if($func == 'readValue'){
 echo readValue();
 }elseif($func == 'storeValue'){
 echo storeValue($val, $datetime);
 }
}

In your date field in your table, set datatype as datetime. Hope this may help.

• binaryBigInt: Doesn't work. I get nothing in my database now. I updated my code.
• Mawia HL: have you checked your console.
• binaryBigInt: It says nothing. I only get a php error that the index funcis not defined but that is a common php warning. The strange thing is that if i do $_GETinstead of $_POST i don't get these warnings and also my getData function, which returns the latest value from the database, works again. So i don't know if it is right to stick with $_POST
• Mawia HL: So from where do you get storeValue. It's not included in your questions. var storeValue=$('#somethingmissing').val()
• Random: @binaryBigInt it is common to say a GET is used for a SELECT, and a POST is used for an INSERT or UPDATE...