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HomeBackend DevelopmentPHP Tutorialphp修改文件上传限制方法汇总_PHP

PHP默认的上传限定是最大2M,想上传超过此设定的文件,需要调整PHP、apache等的一些参数。下面,我们简要介绍一下PHP文件上传涉及到的一些参数:

file_uploads :是否允许通过HTTP上传文件的开关,默认为ON即是开。

upload_tmp_dir :upload_tmp_dir用来说明PHP上传的文件放置的临时目录,要想上传文件,得保证服务器没有关闭临时文件和有对文件夹的写权限,如果未指定则PHP使用系统默认值。

upload_max_filesize :允许上传文件大小的最大值,默认为2M。

post_max_size :控制在采用POST方法进行一次表单提交中PHP所能够接收的最大数据量。如果希望使用PHP文件上传功能,则需要将此值改为比upload_max_filesize要大。

max_input_time :以秒为单位对通过POST、GET以及PUT方式接收数据时间进行限制。如果应用程序所运行环境处在低速链路上,则需要增加此值以适应接收数据所需的更多时间。

memory_limit :为了避免正在运行的脚本大量使用系统可用内存,PHP允许定义内存使用限额。通过memory_limit变量来指定单个脚本程序可以使用的最大内存容量变量memory_limit的值应当适当大于post_max_size的值。

max_execution_time :max_execution_time 设置了在强制终止脚本前PHP等待脚本执行完毕的时间,此时间以秒计算。当脚本进入了一个无限循环状态时此变量非常有用。然而,当存在一个需要很长时间完成的合法活动时(例如上传大型文件),这项功能也会导致操作失败。在这样的情况下必须考虑将此变量值增加,以避免PHP在脚本正在执行某些重要过程的时候将脚本关闭。

对于linux主机,可能在/etc/httpd/conf.d/access.conf/下面里面还有php.conf 文件,这个文件可能会解决一些系统的文件大小限制问题。

以上所述就是本文的全部内容了,希望能够对大家熟练掌握php文件上传有所帮助。

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