Table des matières
The fopen Php function
The Mode parameter in fopen()
Use_include_path parameter
Example #2 – write to a file
Example #3 – append to a file:
Conclusion – PHP Open File

Fichier ouvert PHP

Aug 29, 2024 pm 01:07 PM
php

Modern software solutions require interactions with files. They may require to accept inputs from files or either write output and add it to the file. In either situation, the capability of integrating with files has become an important feature for almost all software that is used to run businesses. In this topic, we are going to learn about PHP Open File. In this tutorial, we will be learning about Php functions that allow us to open files located locally or hosted on a Url and use the file and its content for different purposes.

Start Your Free Software Development Course

Web development, programming languages, Software testing & others

The fopen Php function

The fopen Php function is an in-built function and is used to open files for different purposes in Php.

The syntax of fopen is as below:

fopen ( $filename ,  $mode [$use_include_path = FALSE [,  $context ]] )
Copier après la connexion

In the above syntax,

$filename stands for the name of the file we’d like to open. This could be either a file locally stored or a file hosted on a different server and can be accessed. If the filename is in the form of a Url, then Php will first search for the protocol handler (also known as a wrapper) for that particular protocol. In case if no wrapper is found, Php will then return an error.

If the filename protocol has a registered wrapper, Php will then check if allow_url_fopen is disabled or enabled. If enabled, the fopen will be executed else it will fail with an error message returned.

If a local filename is supplied as $filename, in that case, Php will open a stream to that file. That’s why it’s important to make sure that the file is accessible to Php and the right access is set for the file. You should make sure that safe mode or open_basedir are not activated else further restrictions may apply to access the file.

The syntax for the fopen() Php function is as follows:

<?php
$myFileHandle = fopen("c:\folder\resource.txt", "r");
?>
Copier après la connexion

However, when using a Windows operating system we need to escape any backslashes used in file location or use forward slashes instead.

So the above syntax, when written for a Windows OS, changes to:

<?php
$myFileHandle = fopen("c:\\folder\\resource.txt", "r");
?>
Copier après la connexion

The Mode parameter in fopen()

The mode parameter in fopen() indicates the access level with which the file should be opened. The following different accesses and options are available in php and can be passed as a value for mode:

  1. r: The option “r” is used to open the file is the only read-only mode. It places the file pointer at the start of the file for the purpose of reading.
  2. r+: The option “r+” is used to open the file for both reading and writing purpose. It places the file pointer at the start of the file.
  3. w: It opens the file for writing only. It also places the pointer at the start of the file and truncates the file length to 0. In case if the file doesn’t exist, it will create a new file.
  4. w+: It is used to open the file for both reading and writing purpose. It also places the pointer at the start of the file and truncates the file length to 0. In case if the file doesn’t exist, it will create a new file in the provided location.
  5.  a: It opens the file in write-only mode and places the file pointer to the end. In case if the file is not present, it will create the file with the provided filename.
  6. a+: It opens the file for reading and writing both and places the file pointer to the end. In case if the file is not present, it will create the file with the provided filename.
  7. x: It creates a file for writing purposes only and places the file pointer at the beginning of the file. If the file is already present at the location, fopen() will fail and will return a false value generating an error. If the file does not exist, the fopen function will create it.
  8. x+: It creates a file for both writing as well as reading and places the file pointer at the beginning of the file. If the file is already present at the location, fopen() will fail and will return a false value generating an error. If the file does not exist, the fopen function will create it.
  9.  c: It opens the file in write-only mode. If the file doesn’t exist at the provided location, it will attempt to create one. In case if the file exists, it doesn’t truncate it as compared to “w”. However, it does position the file pointer to the start of the file.
  10. c+: It opens the file for writing and reading mode. If the file doesn’t exist at the provided location, it will attempt to create one. In case if the file exists, it doesn’t truncate it as compared to “w”. However, it does position the file pointer to the start of the file.

Use_include_path parameter

It is an optional input parameter in the fopen() function. It accepts values in Boolean. If provided true, it searched the provided filename in the paths included using include_path too.

The fopen() function returns a file pointer when the file is accessed successfully else will return a False value on failure.

Let’s review a few examples below:

Example #1 – read a file

Let’s create a file with the content “My fopen with read mode example” and place it in the Php ecosystem.

With the below code, let’s attempt to open read the file content.

Code:

<?php
$my_file = fopen("demo.txt", "r") or die("Unable to open file!");
echo fread($my_file,filesize("demo.txt"));
fclose($my_file);
?>
Copier après la connexion

Output:

Fichier ouvert PHP

Example #2 – write to a file

Let’s create and write a file in php with the following example:

Code:

<?php
$myfile = fopen("my_file.txt", "a") or die("Unable to open file!");
$txt = "I know how to write to a file now";
fwrite($my_file, $txt);
$myfile = fopen("my_file.txt", "r") or die("Unable to open file!");
echo fread($my_file,filesize($myfile));
fclose($myfile);
?>
Copier après la connexion

Output:

Fichier ouvert PHP

The above code would also have created a file with the name ”my_file.txt”.

Example #3 – append to a file:

Code:

<?php
$myfile = fopen("my_file.txt", "w") or die("Unable to open file!");
$txt = "I have now added a 2nd line";
fwrite($my_file, $txt);
$myfile = fopen("my_file.txt", "w") or die("Unable to open file!");
echo "I know how to write to a file now";
fclose($myfile);
?>
Copier après la connexion

Output:

Fichier ouvert PHP

Conclusion – PHP Open File

With the above explanation and examples, we can conclude that fopen() can be used for a variety of reading, writing, and appending options. It can be used to operate with the file on the same server as well as a different server.

Ce qui précède est le contenu détaillé de. pour plus d'informations, suivez d'autres articles connexes sur le site Web de PHP en chinois!

Déclaration de ce site Web
Le contenu de cet article est volontairement contribué par les internautes et les droits d'auteur appartiennent à l'auteur original. Ce site n'assume aucune responsabilité légale correspondante. Si vous trouvez un contenu suspecté de plagiat ou de contrefaçon, veuillez contacter admin@php.cn

Article chaud

Combien de temps faut-il pour battre Split Fiction?
3 Il y a quelques semaines By DDD
Repo: Comment relancer ses coéquipiers
3 Il y a quelques semaines By 尊渡假赌尊渡假赌尊渡假赌
Hello Kitty Island Adventure: Comment obtenir des graines géantes
3 Il y a quelques semaines By 尊渡假赌尊渡假赌尊渡假赌
Musée à deux points: toutes les expositions et où les trouver
3 Il y a quelques semaines By 尊渡假赌尊渡假赌尊渡假赌

Article chaud

Combien de temps faut-il pour battre Split Fiction?
3 Il y a quelques semaines By DDD
Repo: Comment relancer ses coéquipiers
3 Il y a quelques semaines By 尊渡假赌尊渡假赌尊渡假赌
Hello Kitty Island Adventure: Comment obtenir des graines géantes
3 Il y a quelques semaines By 尊渡假赌尊渡假赌尊渡假赌
Musée à deux points: toutes les expositions et où les trouver
3 Il y a quelques semaines By 尊渡假赌尊渡假赌尊渡假赌

Tags d'article chaud

Bloc-notes++7.3.1

Bloc-notes++7.3.1

Éditeur de code facile à utiliser et gratuit

SublimeText3 version chinoise

SublimeText3 version chinoise

Version chinoise, très simple à utiliser

Envoyer Studio 13.0.1

Envoyer Studio 13.0.1

Puissant environnement de développement intégré PHP

Dreamweaver CS6

Dreamweaver CS6

Outils de développement Web visuel

SublimeText3 version Mac

SublimeText3 version Mac

Logiciel d'édition de code au niveau de Dieu (SublimeText3)

Date et heure de CakePHP Date et heure de CakePHP Sep 10, 2024 pm 05:27 PM

Date et heure de CakePHP

Guide d'installation et de mise à niveau de PHP 8.4 pour Ubuntu et Debian Guide d'installation et de mise à niveau de PHP 8.4 pour Ubuntu et Debian Dec 24, 2024 pm 04:42 PM

Guide d'installation et de mise à niveau de PHP 8.4 pour Ubuntu et Debian

Téléchargement de fichiers CakePHP Téléchargement de fichiers CakePHP Sep 10, 2024 pm 05:27 PM

Téléchargement de fichiers CakePHP

Routage CakePHP Routage CakePHP Sep 10, 2024 pm 05:25 PM

Routage CakePHP

Discuter de CakePHP Discuter de CakePHP Sep 10, 2024 pm 05:28 PM

Discuter de CakePHP

Configuration du projet CakePHP Configuration du projet CakePHP Sep 10, 2024 pm 05:25 PM

Configuration du projet CakePHP

Guide rapide CakePHP Guide rapide CakePHP Sep 10, 2024 pm 05:27 PM

Guide rapide CakePHP

Comment configurer Visual Studio Code (VS Code) pour le développement PHP Comment configurer Visual Studio Code (VS Code) pour le développement PHP Dec 20, 2024 am 11:31 AM

Comment configurer Visual Studio Code (VS Code) pour le développement PHP

See all articles