how do i validate if my email is already exist?

Question

if(count($_POST)>0) { /* Form Required Field Validation / foreach($_POST as $key=>$value) { 
if(empty($_POST[$key])) {
 $message = ucwords($key) . " field is required"; break; } } / Password Matching Validation */ 

if($_POST['password'] != $_POST['confirm_password']){ $message = 'Passwords should be same '; }

/* Email Validation */ if(!isset($message)) { if (!filter_var($_POST["userEmail"], FILTER_VALIDATE_EMAIL)) { $message = "Invalid UserEmail"; }

}

/* Validation to check if gender is selected */ if(!isset($message)) { if(!isset($_POST["gender"])) { $message = " Gender field is required"; } }

if(!isset($message)) { require_once("dbcontroller.php"); $db_handle = new DBController();

$query = "INSERT INTO users (username, name, last_name, gender, BirthMonth, BirthDay, BirthYear, Country, email, password, phone) VALUES ('" . $_POST["userName"] . "', '" . $_POST["name"] . "', '" . $_POST["lastName"] . "', '" .$_POST["gender"] . "', '" . $_POST["BirthMonth"] . "', '" . $_POST["BirthDay"] . "' , '" . $_POST["BirthYear"] ."','". $_POST["Country"] ."', '" . $_POST["userEmail"]. "','" . $_POST["password"]. "','".$_POST["Phone"]. "')"; $result = $db_handle->insertQuery($query);

Edit: Format the code to visib;e errors better. Thanks in advance to anyone who answers.

sorry..it keeps saying error when i put my code..its my first time asking a question in stackoverflow — chanter rainey, Mar 23 '17 at 07:07
@chanterrainey You probably need to add more text in your post than code only, that's why you get the error(s) from SO. — node_modules, Mar 23 '17 at 07:09
you not even done google for it. there are lot of examples to on how to do it.. — Sahil, Mar 23 '17 at 07:14
Possible duplicate of [How to validate an email address in PHP](http://stackoverflow.com/questions/12026842/how-to-validate-an-email-address-in-php) — Sahil, Mar 23 '17 at 07:16

score 0 · Answer 1 · answered Mar 23 '17 at 07:12

Email Validation: Apart from checking for common symbols like '@' and alpha-numeric, you must also check for white spaces/tabs in start and most importantly convert the incoming input using htmlspecialchars() as:

function reduceInput($data) {
  $data = trim($data);
  $data = stripslashes($data);
  $data = htmlspecialchars($data);
  return $data;
}

Call the reduceInput() function on $_POST['userEmail'] and then use your filter_var() funciton to validate it.

score 0 · Answer 2 · answered Mar 23 '17 at 07:22

0

I understand you mean not to pass exploiting strings to database? You don't have to validate these values for that. There is a php function which will pass the strings safely to your database. That's it:

mysqli_real_escape_string($mysqli_object, $_POST['userName']);

But if you'd like to validate your email and username, do this:

if (ctype_alnum($nick)==false) exit(0);// this makes your nick can only contain letters and numbers
$emailB = filter_var($email, FILTER_SANITIZE_EMAIL);//this sanitizes your email
if ((filter_var($emailB, FILTER_VALIDATE_EMAIL)==false) || ($emailB!=$email)) exit(0);//this validates your email

answered Mar 23 '17 at 07:22

Excalibur

151
3
9

sorry wrong question.. what i mean is that how do i add a condition that will tell if the email i input is already existed in database – chanter rainey Mar 23 '17 at 07:27
ok. I'm now posting the right answer... – Excalibur Mar 23 '17 at 07:29

Shafiqul Islam · Accepted Answer · 2017-03-23T08:38:51.270

0

you want to check that your email is exit in database then use this code. add this code after this line .

/* Email Validation */ if(!isset($message)) { if(!filter_var($_POST["userEmail"], FILTER_VALIDATE_EMAIL))
 { $message = "Invalid UserEmail"; }

  }

your db connection need to connect for this so first connect this

require_once("dbcontroller.php"); $db_handle = new DBController();

hope your connection is ok so this code will check

<?php

$sql = "SELECT anyfiled FROM yourtable WHERE email = " .$_POST['userEmail'];
$select = mysqli_query($con, $sql);
$row = mysqli_fetch_assoc($select);

 if (mysqli_num_rows($select) > 0) {
 $message = "exist";
 }
 ?>

edited Mar 23 '17 at 08:38

answered Mar 23 '17 at 07:34

Shafiqul Islam

5,570
2
34
43

so where will i put this code? should i create a new php file for that? – chanter rainey Mar 23 '17 at 07:37
$sql = "SELECT anyfiled FROM yourtable WHERE email = " .$_POST['userEmail']; $select = mysqli_query($con, $sql); $row = mysqli_fetch_assoc($select); if (mysqli_num_rows > 0) { message = "exist"; } i put this code after the line email validation.now it says , unexpected '=' in C:\xampp\htdocs\final\register.php on line 35 – chanter rainey Mar 23 '17 at 07:56
please check now – Shafiqul Islam Mar 23 '17 at 08:44

how do i validate if my email is already exist?

3 Answers3