PHP Script that checks if email exists in table [duplicate] - php

Question

This question already has answers here:
How to check if a row exists in MySQL? (i.e. check if username or email exists in MySQL)
(4 answers)
Closed 7 years ago.
I'm making a PHP Newsletter script, I'm not very experienced in code, but I try my best to improve, I just need a few ideas in order to make this work.
function validate(){
if(isset($_POST['email'])){
$email = $_POST["email"];
if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
echo "<br>Va rugam introduceti o adresa valida de email";
}else{
return 1;
}
}
}
function checkmail(){
if(validate()==1){
if(isset($_POST['email'])){
$email = $_POST['email'];
$sql = "SELECT * FROM subscribe WHERE email LIKE '$email'";
$connect = new mysqli("localhost", "root", "", "alexandru");
$result = mysqli_query($connect,$sql);
echo print_r($result);
}
}
}
I don't know how I can check the result of the query, I need some ideas, thanks

Answer 1

I have made this simple function which you can use.
function field_exists($field_name, $field_value, $table)
{
global $conn;
try
{
$s = $conn->prepare("SELECT * from $table where $field_name = :f_value");
$s->bindParam(':f_value', $field_value);
$s->execute();
if($s->rowCount() > 0)
{
return true;
}
else
{
return false;
}
}
catch(PDOException $e)
{
echo $e->getMessage();
}
}//function
Using this function, you can check any table for any value of the specified column.
So in your case, the $field_name would be email, $field_value would be $email and table would be subscribers.
Usage
if(field_exists("email", $email, "subscribers"))
{
//email exists
}
else
{
//email doesn't exist
}
The function would return true if this email in the table exists, and false if the email doesn't.

Answer 2

This code i use whithout oops concept in my practicle ithink it'll help
extract($_POST);
$qwe = "SELECT * FROM user_info where email= '$email'";
$result = mysqli_query($con, $qwe);
if (mysqli_fetch_row($result) >= 1) {
header("Location: userreg.php?err=msg");
}
else {
// query for what u want after check mail doesn't exist
}