Jquery JS add html code into a div if empty

<script>
    
    $(document).ready(function(){
       
       function isEmpty( el ){
      return !$.trim(el.html())
  }
  if (isEmpty($('#showvacnt'))) {
     
     $('#showvacnt').append("TEXT GOES HERE.");
     
  }

    });

</script>

php keep form values after submit

<input id="user_name" type="text" pattern="[a-zA-Z0-9]{2,64}" name="user_name" required class="form-control" value="<?php if(isset($_POST['user_name'])) { echo htmlentities ($_POST['user_name']); }?>" />

PHP Display date and time now according to your country (Server time change)

<?php 
       
date_default_timezone_set('Asia/Colombo'); //your country region

http://php.net/manual/en/timezones.php

$timenow = date('H:i:s', time());

$datenow = date('Y-m-d');

?>

Jquery select radio button group value and if else

$("input:radio[name=group1]").click(function() {
var value = $(this).val();
//alert(value);
if(value==='homedelivery'){
$('#payncolcontent').hide();
$('#cashndrcontent').fadeIn();

//alert("222");
}
else if(value==='pickupfromstore'){
//alert("111111");
$('#cashndrcontent').hide();
$('#payncolcontent').fadeIn();
}
});

PHP OOP PDO Database class example

Read / fetch data with PHP PDO Database Connection Class in Simple way

<?php
class db {
    private $username = "root";
    private $password = "";
    function connect() {
        $username = $this->username;
        $password = $this->password;
        try {
            $conn = new PDO('mysql:host=localhost;dbname=test', $username, $password);
        } catch (Exception $ex) {
            die($ex->getMessage());
        }
        return $conn;
    }
}

class getdata extends db {
    function read() {
        $con = $this->connect();
        $sql = "SELECT * FROM CITY";
        try {
            $citylist = $con->query($sql);
        } catch (Exception $ex) {
        }
        return $citylist;
    }
}

$getdataCity = new getdata();
$citylist = $getdataCity->read();

$a = $citylist->fetchAll();

print_r($a);

if($citylist->rowCount()){
    foreach ($a as $city){
        echo $city['city_name'];
    }
}