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HomeBackend DevelopmentPHP TutorialPHP使用feof()函数读文件的方法_PHP

本文实例讲述了PHP使用feof()函数读文件的方法。分享给大家供大家参考。具体用法如下:

feof应用于PHP 4, PHP 5
-用来测试文件指针是否到了文件结束的位置。

如果服务器没有关闭由 fsockopen() 所打开的连接,feof() 会一直等待直到超时而返回TRUE。默认的超时限制是 60 秒,可以使用 stream_set_timeout() 来改变这个值。

文件指针必须是有效的,必须指向由 fopen() 或fsockopen() 成功打开的文件(并还未由fclose() 关闭)。
 
如果传递的文件指针无效可能会陷入无限循环中,因为 EOF 不会返回 TRUE。
Example #1 使用无效文件指针的 feof() 例子:

代码如下:

// 如果文件不可读取或者不存在,fopen 函数返回 FALSE
$file = @fopen("no_such_file", "r");

// 来自 fopen 的 FALSE 会发出一条警告信息并在这里陷入无限循环
while (!feof($file)) {
}
fclose($file);
?>


 
例子:

代码如下:

$file = fopen($_SERVER['DOCUMENT_ROOT']."/me/test.txt", "r"); 
 
//输出文本中所有的行,直到文件结束为止。 
while(! feof($file)) 

  echo fgets($file). "
"; 

fclose($file); 
?>

输出:
Hello, this is a test file.
There are three lines here.
This is the last line.

希望本文所述对大家的PHP程序设计有所帮助。

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