ob_get_contents();ob_end_clean();ob_start();的具体用法
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ob_get_contents();
ob_end_clean(); ob_start() 使用ob_start()把输出那同输出到缓冲区，而不是到浏览器。 然后用ob_get_contents得到缓冲区的数据。 ob_start()在服务器打开一个缓冲区来保存所有的输出。所以在任何时候使用echo ，输出都将被加入缓冲区中，直到程序运行结束或者使用ob_flush()来结束。然后在服务器中缓冲区的内容才会发送到浏览器，由浏览器来解析显示。 函数ob_end_clean 会清除缓冲区的内容，并将缓冲区关闭，但不会输出内容。 此时得用一个函数ob_get_contents()在ob_end_clean()前面来获得缓冲区的内容。 这样的话，能将在执行ob_end_clean()前把内容保存到一个变量中，然后在ob_end_clean()后面对这个变量做操作。 这是EG： ob_start(); // buf1 echo ' multiple '; ob_start(); // buf2 echo ' buffers work '; $buf2 = ob_get_contents(); ob_end_clean(); $buf1 = ob_get_contents(); ob_end_clean(); echo $buf1; echo '<br/>'; echo $buf2; ob_get_contents (PHP 4, PHP 5) ob_get_contents -- Return the contents of the output buffer Description string ob_get_contents ( void ) This will return the contents of the output buffer or FALSE, if output buffering isn't active. See also ob_start() and ob_get_length(). if you use ob_start with a callback function as a parameter, and that function changes ob string (as in example in manual) don't expect that ob_get_contents will return changed ob. it will work as you would use ob_start with no parameter at all. So don't be confused. transfer image, another method (alternative to fsockopen or function socket) : server(192.168.0.1) makeimage.php ........... ........... $nameimage="xxxx.jpg" $comand=exec("plotvelocity.sh $nameimage $paramater1 $paramater2"); ob_start(); readfile($nameimage); $image_data = ob_get_contents(); ob_end_clean(); echo $image_data; unlink($nameimage); Client (192.168.0.2) $bild="images/newimage2.gif"; $host="192.168.0.1"; $url=file_get_contents("http://$host/makeimage.php?$querystring"); $fp = fopen("$bild", 'wb'); fwrite($fp, $url); fclose($fp); echo '<img src="'.$bild.'">'; naturally you can transfer whichever thing and not only images ob_get_clean (PHP 4 >= 4.3.0, PHP 5) ob_get_clean -- Get current buffer contents and delete current output buffer Description string ob_get_clean ( void ) This will return the contents of the output buffer and end output buffering. If output buffering isn't active then FALSE is returned. ob_get_clean() essentially executes both ob_get_contents() and ob_end_clean(). 例子 1. A simple ob_get_clean() example<?php ob_start(); echo "Hello World"; $out = ob_get_clean(); $out = strtolower($out); var_dump($out); ?> Our example will output: string(11) "hello world" See also ob_start() and ob_get_contents(). Notice that the function beneath does not catch errors, so throw in an @ before those ob_* calls Running PHP4 < 4.3.0, you can simply add the following to use the function anyway: <?php if (!function_exists("ob_get_clean")) { function ob_get_clean() { $ob_contents = ob_get_contents(); ob_end_clean(); return $ob_contents; } } ?> |