WordPress禁止用户上传特定类型的文件

如何从WordPress默认允许上传的文件类型中，禁止上传某些特定类型的文件，如WordPress默认允许上传 .exe 后缀名的可运行文件，那么我们怎么禁止用户在WordPress后台发表文章时上传 .exe 后缀名的文件呢？这就是本文要解答的问题。

首先，我们要知道WordPress支持上传哪些类型的文件，我们可以在当前主题的functions.php中插入以下php代码，然后打开博客首页，查看网页源代码，即可看到一个完整的支持列表（记得删除）：

print_r(wp_get_mime_types());

下面是以上代码输出的结果，这里供大家参考，也免了大家去写代码看结果。下面是WordPress默认允许上传的文件类型列表：

// []中括号中的名称代表文件名后缀名/扩展名
// => 后面的名称代表的是后缀名所在应的文件MIME信息
Array
(
    [jpg|jpeg|jpe] => image/jpeg
    [gif] => image/gif
    [png] => image/png
    [bmp] => image/bmp
    [tif|tiff] => image/tiff
    [ico] => image/x-icon
    [asf|asx|wax|wmv|wmx] => video/asf
    [avi] => video/avi
    [divx] => video/divx
    [flv] => video/x-flv
    [mov|qt] => video/quicktime
    [mpeg|mpg|mpe] => video/mpeg
    [mp4|m4v] => video/mp4
    [ogv] => video/ogg
    [mkv] => video/x-matroska
    [txt|asc|c|cc|h] => text/plain
    [csv] => text/csv
    [tsv] => text/tab-separated-values
    [ics] => text/calendar
    [rtx] => text/richtext
    [css] => text/css
    [htm|html] => text/html
    [mp3|m4a|m4b] => audio/mpeg
    [ra|ram] => audio/x-realaudio
    [wav] => audio/wav
    [ogg|oga] => audio/ogg
    [mid|midi] => audio/midi
    [wma] => audio/wma
    [mka] => audio/x-matroska
    [rtf] => application/rtf
    [js] => application/javascript
    [pdf] => application/pdf
    [swf] => application/x-shockwave-flash
    [class] => application/java
    [tar] => application/x-tar
    [zip] => application/zip
    [gz|gzip] => application/x-gzip
    [rar] => application/rar
    [7z] => application/x-7z-compressed
    [exe] => application/x-msdownload
    [doc] => application/msword
    [pot|pps|ppt] => application/vnd.ms-powerpoint
    [wri] => application/vnd.ms-write
    [xla|xls|xlt|xlw] => application/vnd.ms-excel
    [mdb] => application/vnd.ms-access
    [mpp] => application/vnd.ms-project
    [docx] => application/vnd.openxmlformats-officedocument.wordprocessingml.document
    [docm] => application/vnd.ms-word.document.macroEnabled.12
    [dotx] => application/vnd.openxmlformats-officedocument.wordprocessingml.template
    [dotm] => application/vnd.ms-word.template.macroEnabled.12
    [xlsx] => application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
    [xlsm] => application/vnd.ms-excel.sheet.macroEnabled.12
    [xlsb] => application/vnd.ms-excel.sheet.binary.macroEnabled.12
    [xltx] => application/vnd.openxmlformats-officedocument.spreadsheetml.template
    [xltm] => application/vnd.ms-excel.template.macroEnabled.12
    [xlam] => application/vnd.ms-excel.addin.macroEnabled.12
    [pptx] => application/vnd.openxmlformats-officedocument.presentationml.presentation
    [pptm] => application/vnd.ms-powerpoint.presentation.macroEnabled.12
    [ppsx] => application/vnd.openxmlformats-officedocument.presentationml.slideshow
    [ppsm] => application/vnd.ms-powerpoint.slideshow.macroEnabled.12
    [potx] => application/vnd.openxmlformats-officedocument.presentationml.template
    [potm] => application/vnd.ms-powerpoint.template.macroEnabled.12
    [ppam] => application/vnd.ms-powerpoint.addin.macroEnabled.12
    [sldx] => application/vnd.openxmlformats-officedocument.presentationml.slide
    [sldm] => application/vnd.ms-powerpoint.slide.macroEnabled.12
    [onetoc|onetoc2|onetmp|onepkg] => application/onenote
    [odt] => application/vnd.oasis.opendocument.text
    [odp] => application/vnd.oasis.opendocument.presentation
    [ods] => application/vnd.oasis.opendocument.spreadsheet
    [odg] => application/vnd.oasis.opendocument.graphics
    [odc] => application/vnd.oasis.opendocument.chart
    [odb] => application/vnd.oasis.opendocument.database
    [odf] => application/vnd.oasis.opendocument.formula
    [wp|wpd] => application/wordperfect
)

上面的内容，大家看了可能眼花缭乱，其实只要记住，在每一行中，左边中括号中的名称是文件的后缀名（或者叫扩展名），右边 => 后面的名称代表的是后缀名所对应的文件MIME信息，这个我们不用管。

现在言归正传，如果想禁止用户在WordPress后台发表文章时上传特定后缀名的文件，我们可以在当前主题的functions.php中添加以下php代码：

add_filter('upload_mimes', 'custom_upload_mimes');

function custom_upload_mimes( $existing_mimes=array() ) {
  // 注意中括号中的名称，必须取自上面支持列表中中括号内的名称
  unset( $existing_mimes['exe'] ); //此处禁止了上传exe后缀名的文件

  return $existing_mimes; 
}

如果想禁止上传更多后缀名的文件，可以复制第5行的代码，粘贴到第5行代码以后，第7行代码之前，把其中的exe，改成要禁止上传的后缀名即可，如：

add_filter('upload_mimes', 'custom_upload_mimes');

function custom_upload_mimes( $existing_mimes=array() ) {
  // 注意中括号中的名称，必须取自上面支持列表中中括号的名称
  unset( $existing_mimes['exe'] ); //此处禁止了上传exe后缀名的可运行文件
  unset( $existing_mimes['jpg|jpeg|jpe'] ); //此处禁止了上传jpg、jpeg和jpe后缀名的压缩文件
  unset( $existing_mimes['gif'] ); //此处禁止了上传gif后缀名的图片文件
  unset( $existing_mimes['png'] ); //此处禁止了上传png后缀名的图片文件

  return $existing_mimes; 
}

经过此项设置，用户如果在后台上传禁止的文件类型，那么会得到这样的提示：