PHP: header() and include/include_once/require/require_once - PHP: header() and include/include_once/require/require_once

我正在调用header（'Location： http://foo.com/foo/'）;在调用include（）后使用包含函数调用的文件（无输出）的文件中。每当我调用 include（）我时，PHP header（）重定向都不起作用。这只发生在服务器上。无论我包含哪个 PHP 文件，都会发生这种情况。（本地文件在开发过程中上载到服务器。

好吧，实际上我在 DOCTYPE 声明之前得到一个空白字符，这是非常糟糕的！无论我包含一个还是两个文件，我都会得到一个空白字符。

    Neil@NEILCOMPUTER /c/wamp/www/workspace/worknet
    $ curl --verbose http://timescapezonecom.ipage.com/worknet/foo.php
    * About to connect() to timescapezonecom.ipage.com port 80 (#0)
    *   Trying 66.96.147.110... connected
    * Connected to timescapezonecom.ipage.com (66.96.147.110) port 80 (#0)
    > GET /worknet/foo.php HTTP/1.1
    > User-Agent: curl/7.21.1 (i686-pc-mingw32) libcurl/7.21.1 OpenSSL/0.9.8k zlib/1.2.3
    > Host: timescapezonecom.ipage.com
    > Accept: */*
    >
    < HTTP/1.1 302 Found
    < Date: Sun, 08 Jul 2012 23:19:12 GMT
    < Content-Type: text/html; charset=iso-8859-1
    < Content-Length: 206
    < Connection: close
    < Server: Nginx / Varnish
    < X-Powered-By: PHP/5.2.17
    < Set-Cookie: PHPSESSID=0310603f03176770c3feb46ea93d9fd3; path=/
    < Expires: Thu, 19 Nov 1981 08:52:00 GMT
    < Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
    < Pragma: no-cache
    < Location: http://www.google.com
    <
     <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
    <html><head>
    <title>302 Found</title>
    </head><body>
    <h1>Found</h1>
    <p>The document has moved <a href="http://www.google.com">here</a>.</p>
    </body></html>
    * Closing connection #0

另一方面，当我在 foo 中不包含任何文件时.php我在之前得到一个零文档类型，我也觉得奇怪：

    Neil@NEILCOMPUTER /c/wamp/www/workspace/worknet 
    $ curl --verbose http://timescapezonecom.ipage.com/worknet/foo.php
    * About to connect() to timescapezonecom.ipage.com port 80 (#0)
    *   Trying 66.96.147.110... connected
    * Connected to timescapezonecom.ipage.com (66.96.147.110) port 80 (#0)
    > GET /worknet/foo.php HTTP/1.1
    > User-Agent: curl/7.21.1 (i686-pc-mingw32) libcurl/7.21.1 OpenSSL/0.9.8k zlib/1.2.3
    > Host: timescapezonecom.ipage.com
    > Accept: */*
    >
    < HTTP/1.1 302 Found
    < Date: Sun, 08 Jul 2012 23:25:28 GMT
    < Content-Type: text/html; charset=iso-8859-1
    < Content-Length: 206
    < Connection: close
    < Server: Nginx / Varnish
    < X-Powered-By: PHP/5.2.17
    < Set-Cookie: PHPSESSID=98c60264dbcdd024d91bae25db848186; path=/
    < Expires: Thu, 19 Nov 1981 08:52:00 GMT
    < Cache-Control: no-store, no-cache, must-revalidate, post-check=0, pre-check=0
    < Pragma: no-cache
    < Location: http://www.google.com
    <
    0<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
    <html><head>
    <title>302 Found</title>
    </head><body>
    <h1>Found</h1>
    <p>The document has moved <a href="http://www.google.com">here</a>.</p>
    </body></html>
    * Closing connection #0

这是文件foo.php：

    <?php
        session_start();
        // I added the require just to make sure nothing is being printed there
        // (an error for example)
    //    require_once('include/connect.php');
    //   require_once('include/util.php');
        header("Location: " . "http://www.google.com");
        exit;
    ?>

我真的很想知道文件开头的 0 来自哪里。

强烈建议不要对非模板文件使用 php 的结束标记。

<?php //VERY first line, no whit space
  // code
  // NO ?> *anywhere*

通常，是？> 后面的换行符会导致错误。