$_GET['id'] disappears after I press Edit user button and that's why my query for upd-CodePudding

Here's the code from where I am sending id

In this code I am getting ID by using $_GET['id']. At start the $_GET['id'] fetches id and the first query of sql works to fetch the data in input fields but soon as I press EDIT button to update the data than the data stays same in database. I used echo after isset($_POST['edit_user']) but there is nothing in $id.

<?php
session_start();
include("config.php");
//echo $id=$_SESSION['id'];
$id = isset($_GET['id']) ? $_GET['id'] : '';

$sql = "SELECT * FROM phone WHERE id='$id'";
$res = $conn->query($sql);
$row = $res->fetch_assoc();
echo $n = isset($row['name']) ? $row['name'] : '';
echo $phone = isset($row['contacts']) ? $row['contacts'] : '';

if (isset($_POST['edit_user'])) {
    $name = $_POST['fname'];
    $number = $_POST['num'];
    //var_dump($name);
    $sql = "UPDATE phone SET name='$name', contacts='$number' WHERE id='$id'";
    //var_dump($sql);

    //var_dump($res);
    if ($conn->query($sql) == TRUE) {
        echo "<script>alert('You have successfuly updated user') </script>";
        header("location:index.php");
    } else {
        echo "<script>alert('Failed to edit user') </script>";
    }
    $conn->close();
}

?>

<!DOCTYPE html>
<html>

<head>
    <meta charset="utf-8">
    <title>EDIT USER</title>
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/css/bootstrap.min.css">
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.1/js/bootstrap.min.js"></script>
</head>

<body>
    <div >
        <div >
            <div >
                <div ></div>
                <div  jumbotron my-5>
                    <h4 >Edit User</h4>
                    <form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>" method="post">
                        <label>Name</label>
                        <input type="text" name="fname"  autocomplete="off" required value="<?php echo $n ?>">
                        <label>Number</label>
                        <input type="text" name="num"  autocomplete="off" required value="<?php echo $phone ?>">
                        <input type="submit" name="edit_user" value="Edit User" >
                    </form>
                </div>

            </div>
        </div>
    </div>

</body>

</html>

CodePudding user response：

Because when you submit its reloading page so you are missing id in the query string, You just need to pass query string to get data from an URL using $_GET. on your given code you can do this by replacing the action link

$_SERVER["PHP_SELF"]

with

"http://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";

CodePudding user response：

You can us both $_GET and $_POST at the same time but you have to define the

$_GET parameter in the URI like:

<form action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]); ?>?id=21">

or use

$_POST with an hidden input type like:

<input type="hidden" id="id" name="id" value="21">

and you got one more error in the code i ansered here

Remember that header() must be called before any actual output is sent, either by normal HTML tags, blank lines in a file, or from PHP. How to redirect to page with the location?

This will not work:

echo "<script>alert('You have successfuly updated user') </script>";
header("location:index.php");

If you want to alert a message you have to do the alert after location|load the next side something like:

<?php
   if ($conn->query($sql) == TRUE) {
    $ok = 1;
    } 
    else{
    $ok = 2;
   }
   header("location:index.php?ok=$ok");
?>

on the new side do:

<?php
$ok = ($_GET['ok'] ?? '');
if($ok === 1){
echo "<script>alert('You have successfuly updated user')";
}
elseif($ok === 2){
echo "<script>alert('Failed to edit user') </script>";
}
?>

Dont forget your code like this is open for injection malicious code Fix this

CodePudding user response：

since you want to update by using the $_GET['id'], you need to ensure ?id=69 (69 is a dummy id) is present your url when the code runs.

replace your opening form with this:

<form action="./update.php?id=<?=$id?>" method="post">

or:

<form action='<?php echo "http://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";?>' method='post'>