ob_get_length

(PHP 4 >= 4.0.2, PHP 5, PHP 7, PHP 8)

ob_get_length — Devolver la longitud del búfer de salida

Descripción

ob_get_length(): int

Esta función devolverá la longitud del contenido del búfer de salida, en bytes.

Valores devueltos

Devuelve la longitud del contenido del búfer de salida, en bytes, o false si no está activo el almacenamiento en búfer.

Ejemplos

Ejemplo #1 Un ejemplo sencillo de ob_get_length()

<?php

ob_start();

echo "Hola ";

$longitud1 = ob_get_length();

echo "Mundo";

$longitud2 = ob_get_length();

ob_end_clean();

echo $longitud1 . ", ." . $longitud2;
?>

El resultado del ejemplo sería:

5, 10

Ver también

ob_start() - Activa el almacenamiento en búfer de la salida
ob_get_contents() - Devolver el contenido del búfer de salida

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User Contributed Notes 5 notes

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Nitrogen ¶

15 years ago


I use this function to produce a small speed test in my pages since I run my website from my home computers.

<?php
ob_start();
$StartTime=microtime(1);
?>
.. webpage data goes here ..

<?php
// footer?
printf("%s seconds to produce (%skb/sec)",
  microtime(1)-$StartTime,
  Round((ob_get_length()/(microtime(1)-$StartTime))/1024));

ob_end_flush();
?>

Note: don't forget the "speed" depends on how quick the content is actually generated and not on the speed the data is sent to the client..
However it would be good to see such function to get the real speed. :)

Nitrogen.

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rush at logic dot cz ¶

19 years ago


There is a work-around for the situation you need to get length of the gz-ed buffer.

ob_start();
ob_start('ob_gzhandler');

  ... output the page content...

ob_end_flush();  // The ob_gzhandler one

header('Content-Length: '.ob_get_length());

ob_end_flush();  // The main one

more info at http://www.edginet.org/techie/website/http.html

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stangelanda at arrowquick dot com ¶

17 years ago


If you don't buffer your output, it doesn't seem like it would be possible for a web server to output a Content-Length header.  For static files it can check the filesize, but for dynamic files that send output a little by little there is no way to know how many bytes it is going to output.  And the headers have to be sent before a single byte is output.

Also if you're wondering why the Content-Length is important, the browser doesn't close the connection as long as the script is running.  So if you register time consuming shutdown functions, the browser will still 'spin' waiting for more content until they complete.  (I'm not sure this happens under all conditions, but I am certain the sending the Content-Length always prevents this.)

You might take note that this manual page does not currently output any Content-Length header.

Alternatively using mb_strlen($output, 'latin1') seems to work to determine bytes in a string.  strlen may or may not depending on if it has been set up as a multibyte or not.

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Sinured ¶

17 years ago


> Dude, your web server will compute Content-length for you!

I've noticed that Apache 1.3 doesn't do that.
However, if you’re running Apache 2.2 (and maybe 2.0, haven't experienced that yet) you don't need to worry about Content-Length.

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-5

webmaster at crescentart dot com ¶

23 years ago


Here is an easy way to get the header Content-Lenght.

<?

ob_start();

?>



Put HTML tags.



<?

$size=ob_get_length();

header("Content-Length: $size");

ob_end_flush();

?>

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