Code for PHP to check if a file or directory exists

$filename = '/path/to/foo.txt '; if (file_exists ($filename)) { echo "The file $filename exists"; } else { echo "The file $filename does not exist"; } ?> Copy Code If the file is present, the result of executing the PHP file is: The file C:blablaphphello.txt exists. If the files do not exist, the execution of the PHP file displays the result: the file C:\blabla\phphello.txt does not exist. You can also use the File_exists function to test whether a directory exists, sample code: if (file_exists ("C:\blabla\php")) {echo "yes";} Else {echo "No";} ?> Copy Code Instance /** * File or directory permission check function * * @access Public * @param string $file _path file path * @param bool $rename _PRV Check permission to execute rename () function when checking for modify permissions * * @return int return value range is {0 <= x <= 15}, the meaning of each value can be introduced by a combination of four-bit binary numbers. * return value in binary notation, four bits are represented by high to low respectively * Executable Rename () function permission, can append content permission to file, writable file permission, read file permission. */ function File_mode_info ($file _path) { /* If not present, unreadable, non-writable, non-modified */ if (!file_exists ($file _path)) { return false; } $mark = 0; if (Strtoupper (substr (php_os, 0, 3) = = = ' WIN ') { /* Test File */ $test _file = $file _path. '/cf_test.txt '; /* If it is a directory */ if (Is_dir ($file _path)) { /* Check if the directory is readable */ $dir = @opendir ($file _path); if ($dir = = = False) { return $mark; If the directory fails to open, directly returns the directory is non-modifiable, non-writable, unreadable } if (@readdir ($dir)!== false) { $mark ^= 1; Directory readable 001, directory unreadable 000 } @closedir ($dir); /* Check if the directory is writable */ $fp = @fopen ($test _file, ' WB '); if ($fp = = = False) { return $mark; If the file creation in the directory fails, the return is not writable. } if (@fwrite ($fp, ' Directory Access testing. ')!== false) { $mark ^= 2; Directory writable readable 011, directory writable unreadable 010 } @fclose ($FP); @unlink ($test _file); /* Check if the directory can be modified */ $fp = @fopen ($test _file, ' ab+ '); if ($fp = = = False) { return $mark; } if (@fwrite ($fp, "Modify Test.rn")!== false) { $mark ^= 4; } @fclose ($FP); /* Check the directory for permission to execute the rename () function */ if (@rename ($test _file, $test _file)!== false) { $mark ^= 8; } @unlink ($test _file); } /* If it is a file */ ElseIf (Is_file ($file _path)) { /* Open as Read */ $fp = @fopen ($file _path, ' RB '); if ($FP) { $mark ^= 1; Readable 001 } @fclose ($FP); /* Try to modify the file */ $fp = @fopen ($file _path, ' ab+ '); if ($fp && @fwrite ($fp, ')!== false) { $mark ^= 6; Can be modified writable readable 111, non-modifiable writable readable 011 ... } @fclose ($FP); /* Check the directory for permission to execute the rename () function */ if (@rename ($test _file, $test _file)!== false) { $mark ^= 8; } } } Else { if (@is_readable ($file _path)) { $mark ^= 1; } if (@is_writable ($file _path)) { $mark ^= 14; } } return $mark; } ?> Copy Code PHP to determine whether a directory exists example: /*--------------- * XML data stream, written to XML file * @param $xmlData * @return bool|string */ function Writexmlfile ($xmlData) { $time = time (); Gets the timestamp used to name the file $path = DirName (__file__); Gets the current absolute path $path = Substr_replace ($path, "", Stripos ($path, "Actions\data")); Replace the inherent path of this file with an empty $path. = "Xmlfiles\"; Store Directory Name /* Determine if the target directory exists, does not exist, and then new */ if (!is_dir ($path)) { mkdir ($path); New Catalog } /* Record full path and file name */ $filePathAndName = $path. $time. ". XML "; /* Open file with file name <时间戳> + <.xml>*/ $fp = fopen ($filePathAndName, "w"); if (! $fp) { return false; } /* Write to file stream */ $flag = fwrite ($fp, $xmlData); if (! $flag) { return false; } Fclose ($FP); return $filePathAndName; } ?> Copy Code

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