user defined function not working in php [closed]

Question

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center.

Closed 9 years ago.

I have a problem in calling my rand_id() function. here is code as

<?php 
try

{

$config=array(
'DB_USERNAME'=>'root',
'DB_PASSWORD'=>'');


$conn=new PDO('mysql:host=localhost;dbname=scc',$config['DB_USERNAME'],$config['DB_PASSWORD']); 
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

echo rand_id(); 

}

catch(Exception $e)
{
echo 'error: '.$e->getMessage();
}

function rand_id()
{

$id=rand(100,103);          //i have record with id ='100'
$results=$conn->query("select id from student_personal_info where id='".$id."'");

if($results->rowCount()>0)
{   
rand_id();
}
else
{
return "this is unique id";
}
}
?>        

but if I remove the function and check this code working fine but now i can't generate unique id message after checking with database...plz help......

Here is another code after removing function

<?php 

try
{
$config=array(
'DB_USERNAME'=>'root',
'DB_PASSWORD'=>'');

$conn=new PDO('mysql:host=localhost;dbname=scc',$config['DB_USERNAME'],$config['DB_PASSWORD']); 
$conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);


$id=rand(100,103);          //i have record with id ='100'
$results=$conn->query("select id from student_personal_info where id='".$id."'");

if($results->rowCount()>0)
{   
echo  "generate again";
}
else
{
echo  "this is unique id";
}
}
catch(Exception $e)
{
echo 'error: '.$e->getMessage();
}

?>        

Answer 1

Your database object $conn is out of scope in the rand_id() function. You could pass it as an argument:

function rand_id($conn)
{
    // ...
}

Or use the global method:

function rand_id()
{
    global $conn;
    // $conn is now accessible
}

More info about Variable Scope on the Manual.

---

For future debugging, remember to check your error log. In this case you should have something like:

Fatal Error: Call to a member function query() on a non-object in ...