Use of ob_start() and ob_get_clean()

Output Buffer Memory

The ob_start() and ob_get_clean() are used hold the value in the inter buffer memory.

Normal Buffering functions used are.

ob_start();
---------------
This function will turn on the out buffer While buffering is ON no output is sent from script (other then headers), 
instead the output is stored in internal buffer.

ob_get_clean();
------------------
Gets the current output buffer content and delete current output buffer.
Returns the contents of the output buffer and end output buffering. If output buffering isn’t active then FALSE is returned.
Ob_get_clean() executes both ob_get_contents() and ob_end_clean().


ob_end_flush();
------------------
Ends the buffer and sends all data to output.


ob_end_clean();
------------------
Ends the buffer without sending it to output.

Eg:
ob_start();
print “Hello First!\n”;
ob_end_flush();

It will print " Hello First "

ob_start();
print “Hello Second!\n”;
ob_end_clean();

It wont print anything.


ob_start();
echo 'Helloo';
$out = ob_get_clean();

It won't print anything, It will return data to $out variable.