Ajax post not passing data to php? - php

Question

So I'm having trouble with passing data using ajax post to php
Here is my jquery :
$('#kodeobat').on('change',function(){
var kodeobat = $(this).val();
if (kodeobat = ""){
$("#hargaobat").val("");
} else {
$.ajax({
type: "POST",
data: { 'kodeobat': kodeobat },
dataType: "json",
url: "getdata.php",
success: function(json) {
$("#hargaobat").val(json["hargaobat"]);
}
});
}
});
and here is the php file:
$kodeobat = $_POST['kodeobat'];
$stmt = $db_con->prepare("SELECT kodeobat, hargaobat FROM Obat WHERE kodeobat='".$kodeobat."'");
$stmt->execute();
while($row=$stmt->fetchAll(PDO::FETCH_ASSOC))
{
if($kodeobat == $row['kodeobat']){
echo json_encode($row);
}
}
and it results : Notice: Undefined index: kodeobat in .../getdata.php on line 4 which is this line $kodeobat = $_POST['kodeobat'];
Is there something wrong with the code? Thank youuu :)

Answer 1

$('#kodeobat').on('change',function(){
var kodeobat = $(this).val();
if (kodeobat == ""){
$("#hargaobat").val("");
} else {
$.ajax({
type: "POST",
data: { 'kodeobat': kodeobat },
dataType: "json",
url: "getdata.php",
success: function(json) {
$("#hargaobat").val(json["hargaobat"]);
}
});
}
});
Notice if (kodeobat == "")

Answer 2

Try sending your JSON as JSON by using PHP's header() function:
header("Content-Type: application/json", true);
look at this

Answer 3

If you are unaware of what type of value you would get in response here is a try..
$kodeobat = $_POST['kodeobat'];
if(empty($kodeobat)) {
echo("Value is empty");
} else if(is_array($kodeobat)) {
$i = count($kodeobat); //If the value is array iterate it
for($j = 0; $j < $i; $j++) {
echo($kodeobat[$i] . " ");
}
} else if(is_object($kodeobat)){
$json = json_decode($_POST,true); //if it is a json value decode it
$kodeobat_new = $json['kodeobat'];
}