File Management with PHP (
Page 1 of 4 ) We can find many articles related to uploading, viewing, and downloading files. This article is written on the basic concept of uploading and managing files. File uploading is the process of copying the file from your machine to the remote server. Other users of the same system then share this file by viewing or downloading it. What happens when you upload a file that already exists in the remote folder to which you are uploading?While discussing this problem, other issues arise, such as: Should the
program allow the user to restore this file or retain the existing file? If the
file exists, then should I copy the file as a new version? How do I manage
files, if the user uploads files of same name and type more than
once?
Prerequisites To understand this article, you
should have a fair knowledge of PHP. To run examples given in your machine, you
need Apache, PHP, and MySQL installed and configured.
Here's what we
want to accomplish:
- When a user uploads a file for the first time, the system should upload the
file in the specified folder and insert file details (file name, size, and type)
in the database table.
- When the user uploads a file for the second time (the filename has to be the
same), the system will compare the size, date and time of the existing file and
of the file being uploaded, and automatically assign a new version for the
uploaded file if there is a difference. If there is no difference, then the
existing file will be retained and a message will be displayed for the user.
- A check box allows the user to replace the existing file. Clicking this
option will replace the existing file. Note that only the latest version of the
file can be replaced in this case, and not an older one.
- The database will maintain file list and version details. Users should be
able to view all the versions of a file and download the required version.
- While displaying the file list, the program displays all the versions of
files under one name. For example, if the file name is xyz.doc and its other
versions are xyz_VERSION1.doc, xyz_VERSION2.doc, xyz_VERSION3.doc, and so on,
the program will display the filename as xyz.doc for all the versions.
- The program allows users to delete the file. Clicking on delete will ask for
confirmation before proceeding.
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