(PHP 4 >= 4.3.0, PHP 5, PHP 7, PHP 8)
ob_get_flush — 刷出（送出）缓冲区内容，以字符串形式返回内容，并关闭输出缓冲区。
ob_get_flush() 刷出（送出）缓冲区内容，以字符串形式返回内容，并关闭输出缓冲区。
Note: 这个函数与ob_end_flush()相似，不同的是本函数还会以字符串形式返回缓冲区内容。
返回输出缓冲区的内容；或者是，如果没有起作用的输出缓冲区，返回false 。
Example #1 ob_get_flush() example
<?php
//using output_buffering=On
print_r(ob_list_handlers());
//save buffer in a file
$buffer = ob_get_flush();
file_put_contents('buffer.txt', $buffer);
print_r(ob_list_handlers());
?>
以上例程会输出：
Array
(
[0] => default output handler
)
Array
(
)
I don't know how exactly this works, but if you call this function, PHP would behave as if headers have been sent (even though the output has gone to a string).
This means that you can't call this function, and then call setcookie for example.
This was verified by trial and error
Hi,
this is just to add a behavior that I haven't understud at first place.
ob_get_flush actually returns the content of the buffer as a text but also it sends the buffer back to the browser so that it's displayed on user screen.
Use ob_get_clean if you do not want the buffer to be send to the user
Correction to previous post: ob_get_clean() is better, ie:
<?php
// start generating html
$html = '<html><head>'; // etc
// start output buffering
ob_start();
// call function which outputs immediately
print_menu();
// append this to $html and empty buffer
$html .= ob_get_clean();
?>
I found this function is useful for storing output instead of displaying it. For example, I wanted to use an old function which echoed the ouput but I wanted it in a variable, not outputted immediately. Here's how:
<?php
// start generating html
$html = '<html><head>'; // etc
// start output buffering
ob_start();
// call function which outputs immediately
print_menu();
// append this to $html
$html .= ob_get_flush();
// empty output buffer
ob_clean();
?>