php dir function tutorial_PHP tutorial

Listing Documents
Sometimes it's nice to use PHP to list all files in a certain directory. To do this, pass the directory class.

First we have to start with the directory object we want to look at. If in the current directory, use ' . ' since this refers to the current directory.

$dir = dir('.');
?>


The next part is a bit complicated, but that's because PHP's documentation suggests a complicated but short way of doing what we intend.

I'm using a simultaneous control structure that loops through all entries. For the condition, I'm testing if it's a directory - > read() returns false (for the ! == operator which tests for the correct type, so it won't evaluate to 0 or false as it would be with a non-type sensitive operator). I also identified $file within the expression, but transfer will return the last value of the file after the transfer. $dir -> "read()" method will return false in case there are no more files. , it will break the cycle.


while (false !== ($file = $dir->read())) {
echo $file."n";
}
?>


If you are using an html file, you will want to use
instead of a newline so that the file will appear as a new line in your page.
If you executed the code before, you would notice two strange files listed in the output of your script: . and...these are references to the current directory (the '.'), and the parent directory (the '..').

If you want to exclude these from your list, just write a statement that checks if the variable for the file is not one of these values, and if so, ignore it.

while (false !== ($file = $dir->read())) {
if ($file != '.' && $file != '..') {
echo $file."n";
}
}
?>


So it's necessary to close the instance directory level when you're done with them, to clean the resource handles and declare the OS and you're done with it.

$dir->close();
?>


This concludes learning how to list files using PHP. On the next page, you will learn how to upload files from a directory server. On the next page I sent you, however, to actually use being able to retrieve a directory in the archive list, read Kirupa's tutorial on parsing external data.

Yay, this is the last page! In past pages you learned more practical file handling techniques, which we'll summarize on this page.

http://www.bkjia.com/PHPjc/631370.htmlwww.bkjia.comtruehttp: //www.bkjia.com/PHPjc/631370.htmlTechArticleListing Files Sometimes, it is nice to use PHP to list all the files in a certain directory. To do this, pass the directory class. First we have to start with the directory object we want to look at. ...