php安装xdebug后var_dump()不能输变量内容解决办法

有人问为什么php安装xdebug后var_dump()不能输变量内容呢，里面的变量都是直接输出而不是把变量中的内容输出呢，下面我们只要简单的配置一下xdebug即可解决了。

php开发环境里，安装了xdebug模块后，var_dump()输出的结果将比较易于查看，但默认情况下，var_dump() 输出的结果将有所变化：过多的数组元素不再显示，字符串变量将只显示前N个字符，较深的数组元素也被显示成省略号。这点会带来一些不便，我们修改配置文件，设置这些。

在php.ini里的xdebug节点中，加入如下

xdebug.var_display_max_children=128
xdebug.var_display_max_data=512
xdebug.var_display_max_depth=5

详细介绍如下，其中

xdebug.var_display_max_children = 128

参数类型integer，默认值为128

显示对象属性最多个数。多出的不显示

xdebug.var_display_max_data = 512

参数类型integer，默认值512
显示数据最大长度

xdebug.var_display_max_depth = 3

参宿类型integer,默认值为3
显示最大嵌套级数

今天刚配置的php环境结果在php启动时无法加载php_mysql.dll、php_mysqli.dll了，这个我配置是没有问题呀，下面我来给大家介绍php_mysql.dll、php_mysqli.dll无法加载解决方法。

今天启动php环境时，发现mysql模块功能不能使用，网站返回500错误。查看了下apache下错误日志。发现下面一段错误信息：

PHP Warning: PHP Startup: Unable to load dynamic library 'D:/wwwserver/php/ext//php_mysql.dll' - /xd5/xd2/xb2/xbb/xb5/xbd/xd6/xb8/xb6/xa8/xb5/xc4/xc4/xa3/xbf/xe9/xa1/xa3/r/n in Unknown on line 0

这说明php没有成功加载php_mysql.dll这个文件

首先要确保php配置文件php.ini中extension_dir值填写正确，最好使用绝对地址。

如
extension_dir = "D:/wwwserver/php/ext"

如果其他dll加载成功，而php_mysql.dll、php_mysqli.dll加载未成功。

则按下面两种方法解决：

(1)、将php目录下libmysql.dll复制到apache目录下bin子目录中
(2)、apache配置文件httpd.conf 加上下面一段话
LoadFile "D:/wwwserver/php/libmysql.dll"

ps:上面代码LoadFile "D:/wwwserver/php/libmysql.dll" 其中"D:/wwwserver/php/"为php的目录
ps:重启过后还是不行，可能就是版本的问题了，如apache下不要使用vc9版本php。新手就建议下个一键安装包

附另一解决办法

apache下

比如我的apache装在D盘，目录是D:/severs/apache
PHP的目录是D:/servers/php5
这样，把D:/servers/php5/libmysql.dll拷贝到D:/servers/apache/bin这个目录下面
重启apache,问题迎刃而解！~~

iis下：
将php目录下的libmysql.dll复制到c:/windows/system32/目录里面，然后重启iis即可。如果提示正在使用，可以先停止iis(iisreset /stop)即可

当然提示其它dll文件也是一样的解决方法，一般情况下是先检查php目录权限，一般everyone读取，浏览 运行即可。

如果我们安装了php环境但在测试用curl_init()时提示Fatal error: Call to undefined function: curl_init()，这个是证明我们curl没有配置好，下面我来介绍介绍。

调用curl_init()函数测试，出现错误提示如下：
 
Fatal error: Call to undefined function: curl_init()

windowsxp 2003

首先保证你的php已经可以使用，本文不讲解windows下的php配置，只是增加curl的扩展。
1、拷贝PHP目录中的libeay32.dll 和 ssleay32.dll 两个文件到 c:/windows/system32 目录。
2、修改php.ini。去掉 extension = php_curl.dll 前面的分号。
3、重启apache
完成！

windows 7/8/vasta

■You will need to change the extension_dir setting to point to the directory where your extensions lives, or where you have placed your php_*.dll files. For example:

代码如下	复制代码
extension_dir = C:phpextensions

■Enable the extension(s) in php.ini you want to use by uncommenting the extension=php_*.dll lines in php.ini. This is done by deleting the leading ; from the extension you want to load.

Example #1 Enable Bzip2 extension for PHP-Windows

代码如下	复制代码
// change the following line from ... ;extension=php_bz2.dll // ... to extension=php_bz2.dll

今天在php调用session时提示Fatal error: session_start(): Failed to initialize storage module: files(session.inc.php on line 83)错误了，下面我来给各位分享这个问题的处理方法。

原创解决： Fatal error: session_start(): Failed to initialize storage module: files问题

之前编译安装的LNMP环境+phpmyamdin4.02的版本，今天突然出现这个问题：
Fatal error: session_start(): Failed to initialize storage module: files (path: ) in /data/www/phpmyadmin/libraries/session.inc.php on line 83
大致意思是session会话初始化的时候储存路径有误！第一反应就是查看php.ini的配置文件中的：

代码如下	复制代码
session.save_path = "/tmp"

默认前面是加的分号，表示不启用，我之前配置的时候已经启用了。那为什么还会报错呢？，于是网上找了一些资料，感觉都千篇一律：
1、检查error.log(Apache2.2logs)文件，查看是否有错误报告。未发现。

2、检查php.ini中的session.save_handler的值是否为files，如果不是改为files

3、检查php.ini文件中session.save_path是否被注释了，如果有，则去掉前面的”;”。

4、将save_path后面的路径改成已有的路径，比如”D:phptemp”

5、检查temp文件夹的属性是否可读可写。

6、重启APACHE服务器。OK
不知道那些哥们转载的时候自己试过了没有（在这里喷一下，最讨厌那种自己都没有亲测，就一股脑的转来转去。一点都不负责!）
根据上面的流程，排查了之后发现压根就没有解决，不过璞玉的服务器是nginx非apache。
然后自己写了一个脚本test.php：
   $r = session_start();  var_dump($r);
打印结果为：
Warning: session_start(): SAFE MODE Restriction in effect. The script whose uid is 501 is not allowed to access /tmp owned by uid 0 in /data/www/test.php on line 3 Fatal error: session_start(): Failed to initialize storage module: files (path: ) in /data/www/test.php on line 3
意思是 php5一个安全模式的bug，默认session的save_path是系统的临时目录，这样会要校验权限。而这个脚本不能通过/tmp拥有者uid为0来执行uid是501也是www用户组的权限
解决这个有两种解决方法：
1。关闭安全模式；

2。在命令行下chown改文件/目录的拥有者

当然两种方法都要求你有服务器的权限。

下面是璞玉php.ini的配置文件：
[Session]
 ; Handler used to store/retrieve data.
 ; http://php.net/session.save-handler
session.save_handler = files; Argument passed to save_handler.  In the case of files, this is the path
 ; where data files are stored. Note: Windows users have to change this
 ; variable in order to use PHP's session functions.
 ;
 ; The path can be defined as:
 ;
 ;     session.save_path = "N;/path"
 ;
 ; where N is an integer.  Instead of storing all the session files in
 ; /path, what this will do is use subdirectories N-levels deep, and
 ; store the session data in those directories.  This is useful if you
 ; or your OS have problems with lots of files in one directory, and is
 ; a more efficient layout for servers that handle lots of sessions.
 ;
 ; NOTE 1: PHP will not create this directory structure automatically.
 ;         You can use the script in the ext/session dir for that purpose.
 ; NOTE 2: See the section on garbage collection below if you choose to
 ;         use subdirectories for session storage
 ;
 ; The file storage module creates files using mode 600 by default.
 ; You can change that by using
 ;
 ;     session.save_path = "N;MODE;/path"
 ;
 ; where MODE is the octal representation of the mode. Note that this
 ; does not overwrite the process's umask.
 ; http://php.net/session.save-path
 session.save_path = "/tmp"
; Whether to use cookies.
 ; http://php.net/session.use-cookies
 session.use_cookies = 1
; http://php.net/session.cookie-secure
 ;session.cookie_secure =
; This option forces PHP to fetch and use a cookie for storing and maintaining
 ; the session id. We encourage this operation as it's very helpful in combatting
 ; session hijacking when not specifying and managing your own session id. It is
 ; not the end all be all of session hijacking defense, but it's a good start.
 ; http://php.net/session.use-only-cookies
 session.use_only_cookies = 1
; Name of the session (used as cookie name).
 ; http://php.net/session.name
 session.name = PHPSESSID
; Initialize session on request startup.
 ; http://php.net/session.auto-start
 session.auto_start = 0
; Lifetime in seconds of cookie or, if 0, until browser is restarted.
 ; http://php.net/session.cookie-lifetime
 session.cookie_lifetime = 0
; The path for which the cookie is valid.
 ; http://php.net/session.cookie-path
 session.cookie_path = /
; The domain for which the cookie is valid.
 ; http://php.net/session.cookie-domain
 session.cookie_domain =
; Whether or not to add the httpOnly flag to the cookie, which makes it inaccessible to browser scripting languages such as JavaScript.
 ; http://php.net/session.cookie-httponly
 session.cookie_httponly =
; Handler used to serialize data.  php is the standard serializer of PHP.
 ; http://php.net/session.serialize-handler
 session.serialize_handler = php
; Defines the probability that the 'garbage collection' process is started
 ; on every session initialization. The probability is calculated by using
 ; gc_probability/gc_divisor. Where session.gc_probability is the numerator
 ; and gc_divisor is the denominator in the equation. Setting this value to 1
 ; when the session.gc_divisor value is 100 will give you approximately a 1% chance
 ; the gc will run on any give request.
 ; Default Value: 1
 ; Development Value: 1
 ; Production Value: 1
 ; http://php.net/session.gc-probability
 session.gc_probability = 1
; Defines the probability that the 'garbage collection' process is started on every
 ; session initialization. The probability is calculated by using the following equation:
 ; gc_probability/gc_divisor. Where session.gc_probability is the numerator and
 ; session.gc_divisor is the denominator in the equation. Setting this value to 1
 ; when the session.gc_divisor value is 100 will give you approximately a 1% chance
 ; the gc will run on any give request. Increasing this value to 1000 will give you
 ; a 0.1% chance the gc will run on any give request. For high volume production servers,
 ; this is a more efficient approach.
 ; Default Value: 100
 ; Development Value: 1000
 ; Production Value: 1000
 ; http://php.net/session.gc-divisor
 session.gc_divisor = 1000
; After this number of seconds, stored data will be seen as 'garbage' and
 ; cleaned up by the garbage collection process.
 ; http://php.net/session.gc-maxlifetime
 session.gc_maxlifetime = 1440
; NOTE: If you are using the subdirectory option for storing session files
 ;       (see session.save_path above), then garbage collection does *not*
 ;       happen automatically.  You will need to do your own garbage
 ;       collection through a shell script, cron entry, or some other method.
 ;       For example, the following script would is the equivalent of
 ;       setting session.gc_maxlifetime to 1440 (1440 seconds = 24 minutes):
 ;          find /path/to/sessions -cmin +24 | xargs rm
; PHP 4.2 and less have an undocumented feature/bug that allows you to
 ; to initialize a session variable in the global scope, even when register_globals
 ; is disabled.  PHP 4.3 and later will warn you, if this feature is used.
 ; You can disable the feature and the warning separately. At this time,
 ; the warning is only displayed, if bug_compat_42 is enabled. This feature
 ; introduces some serious security problems if not handled correctly. It's
 ; recommended that you do not use this feature on production servers. But you
 ; should enable this on development servers and enable the warning as well. If you
 ; do not enable the feature on development servers, you won't be warned when it's
 ; used and debugging errors caused by this can be difficult to track down.
 ; Default Value: On
 ; Development Value: On
 ; Production Value: Off
 ; http://php.net/session.bug-compat-42
 session.bug_compat_42 = Off
; This setting controls whether or not you are warned by PHP when initializing a
 ; session value into the global space. session.bug_compat_42 must be enabled before
 ; these warnings can be issued by PHP. See the directive above for more information.
 ; Default Value: On
 ; Development Value: On
 ; Production Value: Off
 ; http://php.net/session.bug-compat-warn
 session.bug_compat_warn = Off
; Check HTTP Referer to invalidate externally stored URLs containing ids.
 ; HTTP_REFERER has to contain this substring for the session to be
 ; considered as valid.
 ; http://php.net/session.referer-check
 session.referer_check =
; How many bytes to read from the file.
 ; http://php.net/session.entropy-length
 session.entropy_length = 0
; Specified here to create the session id.
 ; http://php.net/session.entropy-file
 ; On systems that don't have /dev/urandom /dev/arandom can be used
 ; On windows, setting the entropy_length setting will activate the
 ; Windows random source (using the CryptoAPI)
 ;session.entropy_file = /dev/urandom
; Set to {nocache,private,public,} to determine HTTP caching aspects
 ; or leave this empty to avoid sending anti-caching headers.
 ; http://php.net/session.cache-limiter
 session.cache_limiter = nocache
; Document expires after n minutes.
 ; http://php.net/session.cache-expire
 session.cache_expire = 180
; trans sid support is disabled by default.
 ; Use of trans sid may risk your users security.
 ; Use this option with caution.
 ; - User may send URL contains active session ID
 ;   to other person via. email/irc/etc.
 ; - URL that contains active session ID may be stored
 ;   in publically accessible computer.
 ; - User may access your site with the same session ID
 ;   always using URL stored in browser's history or bookmarks.
 ; http://php.net/session.use-trans-sid
 session.use_trans_sid = 0
; Select a hash function for use in generating session ids.
 ; Possible Values
 ;   0  (MD5 128 bits)
 ;   1  (SHA-1 160 bits)
 ; This option may also be set to the name of any hash function supported by
 ; the hash extension. A list of available hashes is returned by the hash_algos()
 ; function.
 ; http://php.net/session.hash-function
 session.hash_function = 0
; Define how many bits are stored in each character when converting
 ; the binary hash data to something readable.
 ; Possible values:
 ;   4  (4 bits: 0-9, a-f)
 ;   5  (5 bits: 0-9, a-v)
 ;   6  (6 bits: 0-9, a-z, A-Z, "-", ",")
 ; Default Value: 4
 ; Development Value: 5
 ; Production Value: 5
 ; http://php.net/session.hash-bits-per-character
 session.hash_bits_per_character = 5
; The URL rewriter will look for URLs in a defined set of HTML tags.
 ; form/fieldset are special; if you include them here, the rewriter will
 ; add a hidden <input> field with the info which is otherwise appended
 ; to URLs.  If you want XHTML conformity, remove the form entry.
 ; Note that all valid entries require a "=", even if no value follows.
 ; Default Value: "a=href,area=href,frame=src,form=,fieldset="
 ; Development Value: "a=href,area=href,frame=src,input=src,form=fakeentry"
 ; Production Value: "a=href,area=href,frame=src,input=src,form=fakeentry"
 ; http://php.net/url-rewriter.tags
 url_rewriter.tags = "a=href,area=href,frame=src,input=src,form=fakeentry"因为这个是在一台VPS上面配置的，上面有多个项目，于是璞玉打开一个项目，发现此项目的验证码功能是OK的。
于是查看代码如下：

代码如下	复制代码
$sessSavePath = "/data/sessions/";  // Session保存路径  if(is_writeable($sessSavePath) && is_readable($sessSavePath)){ session_save_path($sessSavePath); }  if(!empty($cfg_domain_cookie)) session_set_cookie_params(0,'/',$cfg_domain_cookie);

上面这个代码是在session_start() 初始化之前来判断是否存在session会话的文件夹。
于是就在phpmyadmin里面的保存的那个文件/phpmyadmin/libraries/session.inc.php做了下修改:

代码如下

复制代码

if (! isset($_COOKIE[$session_name])) {  // on first start of session we check for errors  // f.e. session dir cannot be accessed - session file not created  $orig_error_count = $GLOBALS['error_handler']->countErrors();  //session_save_path('./tmp');  session_save_path("/data/www/session");  $r = session_start();  if ($r !== true  || $orig_error_count != $GLOBALS['error_handler']->countErrors()  ) {  setcookie($session_name, '', 1);  /*  * Session initialization is done before selecting language, so we  * can not use translations here.  */  PMA_fatalError('Cannot start session without errors, please check errors given in your PHP and/or webserver log file and configure your PHP installation properly. Also ensure that cookies are enabled in your browser.');  }  unset($orig_error_count);  } else {  session_save_path("/data/www/session");  session_start();  }

在    session_start();  前面添加了  session_save_path(“/data/www/session”); 就解决了这个问题。
切记通过@ini_set(‘session.save_path’, ”/data/www/session”);无效！
这个问题困扰了我几个小时，终于解决了，所以就记录下来，对日后应该会有帮助。
如果对你有帮助，请留言。如果有什么意见欢迎交流！

fopen函数在php中多半是用于读写文件了，但有时也用于获取远程服务器的文件，但我们在使用fopen读取远程文件时需要开启allow_url_fopen才可以哦。

解决过程

首先排除了DNS的问题，因为除了这几个函数，其他一切工作正常。虽然是带域名的URL才有问题，但gethostbyname() 这个函数却可以得到正确返回。 然后想到的是php.ini 的配置问题——但发现allow_url_fopen 已经打开。 之后寻求Google帮忙，有人提及是SELINUX的问题。可我压根没有打开SELINUX。继续Google之，发现了StackOverflow的这篇

代码如下

复制代码

$file = fopen('http://www.google.com/', 'rb'); var_dump(stream_get_meta_data($file)); /* 输出结果： array(10) {   ["wrapper_data"]=>   array(2) {     ["headers"]=>     array(0) {     }     ["readbuf"]=>     resource(38) of type (stream)   }   ["wrapper_type"]=>   string(4) "cURL"   ["stream_type"]=>   string(4) "cURL"   ["mode"]=>   string(2) "rb"   ["unread_bytes"]=>   int(0)   ["seekable"]=>   bool(false)   ["uri"]=>   string(23) "http://www.google.com/"   ["timed_out"]=>   bool(false)   ["blocked"]=>   bool(true)   ["eof"]=>   bool(false) }*/

要使用fopen、getimagesize或include等函数打开一个url，需要对php.ini进行设置，通常设置allow_url_fopen为on允许fopen url，设置allow_url_include为on则允许include/require url，但在本地测试环境下却不一定管用

allow_url_fopen = on

Whether to allow the treatment of URLs (like http:// or ftp://) as files.

allow_url_include = on

Whether to allow include/require to open URLs (like http:// or ftp://) as files.

在本地wamp测试环境中，这样设置以后，fopen可以正常打开远程地址，但遇到本地的地址却会报错，例如

代码如下	复制代码
1 fopen("http://localhost/myfile.php", "r");

就会在超过php.ini中设置的脚本最长执行时间后报错，告知文件不存在等。这在在线服务器上是不会出现的，但如果将localhost替换成127.0.0.1，却可以正常工作。

从状况看，问题出在DNS解析上，按理说localhost已经自动被映射到127.0.0.1，实际上访问http://localhost和访问http://127.0.0.1也到达同一个地址。

解决的方法就是检查一下Windows的host文件，通常位于system32目录下，一个系统盘是C盘的host路径如下所示

代码如下	复制代码
C:/Windows/System32/drivers/etc/hosts

打开hosts文件，用记事本或者notepad++等工具

将下面的127.0.0.1前面的#去掉即可。

代码如下	复制代码
# localhost name resolution is handled within DNS itself. #   127.0.0.1       localhost

将url视为文件有什么用
比如给include的文件传值，可以这样

代码如下	复制代码
<?php include 'http://yourdomain.com/ example.inc.php?foo=1&bar=2'; ?>

在example.inc.php中

代码如下	复制代码
<?php     var_dump($_GET['foo']);    var_dump($_GET['bar']); ?>

运行结果

string(1) "1" string(1) "2"