


How to use the php function mkdir to create a multi-level directory_PHP tutorial
When we want to add multi-level directories on our website, we can use php function mkdir parameters and description
path is required. Specifies the name of the directory to be created.
mode required. Specify permissions. The default is 0777.
recursive required. Specifies whether to set recursive mode.
context required. Specifies the environment for a file handle. Context is a set of options that modify the behavior of the stream.
Explanation
php function mkdir attempts to create a new directory specified by path.
The default mode is 0777, which means maximum possible access.
PHP’s default mkdir can only create one layer of directories at a time. If you create a div/css/layout directory in the current directory, you need to create the div layer by layer first, then create the div/css and then create it. div/css/layout, however we hope to have the program automatically complete this process for us.
In fact, the idea is very simple, 1. First determine whether the div directory exists, and create it if it does not exist; 2. Determine whether the subdirectory div/css exists, and create it if it does not exist. 3. In the second step, use The function itself is called recursively with the subdirectory as argument. You can also proceed in reverse order, 1. First determine whether the bottom directory div/css/layout exists; 2. Determine whether the upper directory div/css of div/css/layout exists. If it does not exist, use div/css as a parameter to proceed recursively. . .
The following is the program code of php function mkdir:
<ol class="dp-xml"> <li class="alt"><span><span>function mkdirs($dir) </span></span></li> <li><span>{ </span></li> <li class="alt"><span>if(!is_dir($dir)) </span></li> <li><span>{ </span></li> <li class="alt"><span>if(!mkdirs(dirname($dir))){ </span></li> <li><span>return false; </span></li> <li class="alt"><span>} </span></li> <li><span>if(!mkdir($dir,0777)){ </span></li> <li class="alt"><span>return false; </span></li> <li><span>} </span></li> <li class="alt"><span>} </span></li> <li><span>return true; </span></li> <li class="alt"><span>} </span></li> <li><span>mkdirs('div/css/layout'); </span></li> <li class="alt"><span>同样的思路,php用rmdir和unlink递归删除多级目录的代码: </span></li> <li><span>function rmdirs($dir) </span></li> <li class="alt"><span>{ </span></li> <li> <span>$</span><span class="attribute">d</span><span> = </span><span class="attribute-value">dir</span><span>($dir); </span> </li> <li class="alt"> <span>while (false !== ($</span><span class="attribute">child</span><span> = $d-</span><span class="tag">></span><span>read())){ </span> </li> <li><span>if($child != '.' && $child != '..'){ </span></li> <li class="alt"><span>if(is_dir($dir.'/'.$child)) </span></li> <li><span>rmdirs($dir.'/'.$child); </span></li> <li class="alt"><span>else unlink($dir.'/'.$child); </span></li> <li><span>} </span></li> <li class="alt"><span>} </span></li> <li> <span>$d-</span><span class="tag">></span><span>close(); </span> </li> <li class="alt"><span>rmdir($dir); </span></li> <li><span>} </span></li> </ol>
The above code example is the specific implementation of php function mkdir to create multi-level directories method.

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