Question posted in 
I want to send an Ajax request when clicking a button but it seems my request is never executed.
Here is my HTML code :
<!DOCTYPE html>
<html lang="en">
<head>
<title>User Form</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.16.0/umd/popper.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js"></script>
<script src = "./actions.js"></script>
</head>
<body>
<div id="badFrm" class="container">
<h2><br>User Registration</h2>
<form id="Form" method="post">
<div class="form-group">
<label for="name">Name:</label>
<input type="name" class="form-control" id="name" placeholder="Enter Name" name="name">
</div>
<div class="form-group">
<label for="email">Email:</label>
<input type="email" class="form-control" id="email" placeholder="Enter Email" name="email">
</div>
<button id="submitBtn" class="btn btn-primary">Submit</button>
</form>
</div>
</body>
</html>
i feel there is something wrong with my javascript code but i cant figure whats wrong ! i changed a lot of it based on the comments i got earlier . what i want is when i click on the update button it changes to " submit again " and i want to replace "list items" ( name and email ) with input fields and put whatever written in them to be saved in the database instead . and eventually return to the first page which is the register form. i need help in this part !! i know this part is buggy . i need to know how to reach each list item individually ( what attribute should i add/use )
and here is my javascript code :
$(document).ready(function() {
var i ;
$("#submitBtn").click(function (e) {
e.preventDefault();
var name = $("#name").val();
var email = $("#email").val();
$.post("http://localhost/MiniProject/connect.php",
{
name: name,
email: email
}, function () {
var element = document.getElementById("badFrm");
element.remove();
showTbl();
});
function showTbl() {
$.post("http://localhost/MiniProject/Select.php",
{
name: name,
email: email
}, function (res) {
// console.log(res);
res = JSON.parse(res);
var html = '<ul id="List">';
for (i = 0; i < res.length; i++) {
var j = i +1 ;
html += '<li class = "name" >' + res[i].name + '</li><li class = "email">' + res[i].email + '</li>'+ '<div>' + '<button onclick="removeUser(this)" class="btn btn-primary">Remove</button>' + '<button onclick="updateUser(this)" class="btn btn-primary">Update</button>' + '</div>';
}
html += '</ul>';
document.body.innerHTML = html;
});
}
});
});
function removeUser(element){
var ID = element.id;
var element2 = document.getElementById("List");
element2.remove();
$.post("http://localhost/MiniProject/Remove.php",{
id : ID
}, function (res) {
console.log(res);
document.write(res);
});
//alert(element.id);
}
function updateUser(element){
// code ...
$.post("http://localhost/MiniProject/Update.php",{
id : ID2,
}, function (res) {
console.log(res);
// document.write(res);
});
}
here is connect.php :
<?php
require 'Users.php';
$name = $_POST['name'];
$email = $_POST['email'];
$conn = new mysqli('localhost','root','','mydatabasename');
if($conn->connect_error){
die('Connection Failed : '.$conn->connect_error);
}else {
$user = new Users();
$user->Insert(['name' => $name, 'email' => $email]);
echo "name is : ".$name." and email is : ".$email;
}
this is Users.php :
<?php
require 'newDB.php';
class Users extends DatabaseClass{
public $table = 'Users';
}
and this is where i handle the database commands :
<?php
class DatabaseClass{
public $connection = null;
public $table = null;
// this function is called everytime this class is instantiated
public function __construct( $dbhost = "localhost", $dbname = "myDatabaseName", $username = "root", $password = ""){
try{
// $conn = new PDO("mysql:host=$servername;dbname=$dbname", $username, $password);
$this->connection = new PDO("mysql:host=$dbhost;dbname=$dbname", $username, $password);
$this->connection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
$this->connection->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
$sql = "CREATE TABLE MyGuests (
id INT(6) UNSIGNED AUTO_INCREMENT PRIMARY KEY,
firstname VARCHAR(30) NOT NULL,
lastname VARCHAR(30) NOT NULL,
email VARCHAR(50),
reg_date TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
)";
}catch(Exception $e){
throw new Exception($e->getMessage());
}
}
// Insert a row/s in a Database Table
public function Insert($parameters = [] ){
try{
$fields = array_keys($parameters);
$fields_string = '`' . implode('`,`', $fields) . '`';
$values_string = ':' . implode(',:', $fields);
$sql = "INSERT INTO `{$this->table}`({$fields_string}) VALUES ( {$values_string} )";
$this->executeStatement( $sql , $parameters );
return $this->connection->lastInsertId();
}catch(Exception $e){
throw new Exception($e->getMessage());
}
}
// Select a row/s in a Database Table
public function Select( $parameters = [] ){
try{
$fields = array_values($parameters);
$fields_string=implode(' , ',$fields);
$sql = "SELECT {$fields_string} FROM {$this->table}";
$stmt = $this->executeStatement( $sql , $parameters );
return $stmt->fetchAll();
}catch(Exception $e){
throw new Exception($e->getMessage());
}
}
// Update a row/s in a Database Table
public function Update( $parameters = [] ){
try{
$fields = array_keys($parameters);
$fields_string = 'id = '.implode($fields);
$sql = "UPDATE {$this->table} SET {$fields_string} WHERE {$fields_string} ";
echo $sql; exit ;
$this->executeStatement( $sql , $parameters );
}catch(Exception $e){
throw new Exception($e->getMessage());
}
}
// Remove a row/s in a Database Table
public function Remove( $parameters ){
try{
$fields_string = 'id = '.implode($parameters);
$sql = "DELETE FROM {$this->table} WHERE {$fields_string}";
$this->executeStatement( $sql , $parameters );
}catch(Exception $e){
throw new Exception($e->getMessage());
}
}
// execute statement
public function executeStatement( $statement = "" , $parameters = [] ){
try{
$stmt = $this->connection->prepare($statement);
$stmt->execute($parameters);
return $stmt;
}catch(Exception $e){
throw new Exception($e->getMessage());
}
}
}
and this is Update.php :
<?php
require 'Users.php';
$id = $_POST['id'];
$conn = new mysqli('localhost','root','','mydatabasename');
if($conn->connect_error){
die('Connection Failed : '.$conn->connect_error);
}else {
$user = new Users();
$result = $user->Update(['id'=>$id]);
// echo json_encode($result);
}
?>
i dont want the question to have a lot of code so hope this makes it better to understand.
2
Answers
You say that you want to make an AJAX request (submit), but I don’t see where are you doing it.
Also, it seems that you’re submitting twice your form.
You should have something like this:
$(this).serialize() will work only if you change your button to a submit input:
you can also use a "button" but then you’ll have to specify what data you’re submitting, it’s easier to use a submit input, if you ask me.
Also, if you already have an ID for name and email, it’s a lot easier to change them using it’s respective ID’s, instead of trying to re-write the whole div element.
Anyway, I hope it helps
I mentioned posting something without jQuery – here is a demo which does what I understand your requirement to be. There are comments below to explain what is going on.