PHP File Handling Examples

Read, write, delete & modify files effortlessly with built-in file handling functions. Learn all the techniques of PHP File Handling and streamline your file manipulation process:

In this tutorial, you will learn file manipulation in PHP with related functions like PHP fopen, PHP file uploading, and some frequently asked questions (FAQs) related to PHP file handling.

Please note that we have used PHP version 7 in all examples.

Let’s begin!

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File Handling in PHP: Simple Guide

PHP File Manipulation

Sometimes, we have to work with external files when developing software. It may read data from an external file or writing data into an external file, etc. PHP facilitates users to manipulate files by writing a few code lines.

PHP has several built-in functions for file manipulation.

Some of the important file manipulation functions are shown in the list below:

• Create a file – fopen()
• Output a file – readfile()
• Open a file – fopen()
• Read a file – fread()
• Close a file – fclose()
• Write a file – fwrite()
• Append a file – fwrite()
• Delete a file – unlink()

=>> Visit this link to find the full list

Note: It may be a little confusing, as some functions are used for multiple purposes. For example, the fopen() function is used to open a file as well as to create a file.

Create a File – fopen()

PHP fopen() function is used to create a file. It has two mandatory parameters:

• 1^st parameter – the name of the file to be created
• 2^nd parameter – file open mode

There are six file open modes available to create a file. These are listed in the table below:

An example is shown below. You can practice this example by running the following programming code:

<?php 
 
fopen("new.txt","w");
 
?>

Output:

It will create a file called new.txt in your project folder.

Note: In this example, we use the file mode, w. Therefore, if there is already a file called new.txt in your project folder, it will be deleted, and a new file with the same file name will be created. You may practice this example using other file modes as well.

Output a File – readfile()

The readfile() function is used to output a file. If the function is successfully executed, it returns the number of bytes read from the file. Otherwise, it returns false.

To read a file, it must be created.

An example is shown below. You can practice this example by running the following programming code.

First, you need to create a file called sample.txt with the following content in your project folder.

Hello World

You may use any file name, type (text file or HTML file), and/or content.

Create another file with the following code and run it.

<?php 
 
echo readfile("sample.txt");
 
?>

Output:

Hello World11

In the above output, 11 is the number of bytes reads from the file, sample.txt.

Open, Read and Close a File – fopen(), fread() & fclose()

The fopen() function is used to open a file (or a URL).

It has two mandatory parameters:

• 1^st parameter – file name to be opened
• 2^nd parameter – file open mode

There are eight file open modes available to open a file. They are listed in table below:

The fread() function is used to read a file. It is also known as binary-safe file read. To read a file, it must be opened. The fread() function has two mandatory parameters.

• 1^st parameter – stream/source
• 2^nd parameter – number of bytes to be read

The fclose() function is used to close the file.

An example is shown below. You can practice this example by running the following programming code.

You need to have a file called sample.txt with the following content in your project folder.

Hello World

Create another file with the following code and run it.

<?php 
 
$f = fopen("sample.txt","r");
echo fread($f,5);
fclose($f);
 
?>

Output:

Hello

Five bytes have been read from the file sample.txt.

Write and Append a File – fwrite()

The fwrite() function is used to write/append a file.

To write/append a file, it must be opened.

A few examples are shown below. You can practice these examples by running the following programming codes.

Example 1: Write a file – When there is no existing file called sample.html in your project folder

<?php 
 
$f = fopen("sample.html","w");
fwrite($f, "John Doe");
fclose($f);
 
?>

Output:

It will create a file called sample.html with the following content in your project folder.

John Doe

Example 2: Write a file – When there is an existing file called sample.txt in your project folder

You need to have a file called sample.txt with the following content in your project folder.

Hello World

Create another file with the following code and run it.

<?php 
 
$f = fopen("sample.txt","w");
fwrite($f, "Welcome to Software Testing Help!");
fclose($f);
 
?>

Output:

It will delete the existing sample.txt file and create a new file with the same name with the following content.

Welcome to Software Testing Help!

Example 3: Append a file – When there is an existing file called welcome.html in your project folder

First, create a file called welcome.html with the following content in your project folder.

Welcome,

Create another file with the following code and run it.

<?php 
 
$f = fopen("welcome.html","a");
fwrite($f, " John Doe!");
fclose($f);
 
?>

Output:

It will append the content, John Doe!, to the welcome.html file as shown below.

Welcome, John Doe!

Delete a File – unlink()

The unlink() function is used to delete a file. If the file is successfully deleted, outputs 1 (only if you use the echo statement) and if the file is not found, outputs a warning.

A few examples are shown below. You can practice these examples by running the following programming codes.

Example 1: Delete an existing file

Note: You should have a file called sample.txt in your project folder.

<?php 
 
echo unlink("sample.txt");
 
?>

Output:

1

sample.txt will be deleted from your project folder.

Example 2: Trying to delete a non-existing file

Note: newsample.txt is non-existing.

<?php 
 
echo unlink("newsample.txt");
 
?>

Output:

Warning: unlink(newsample.txt): No such file or directory in C:\laragon\www\index.php on line 3

PHP File Upload

PHP allows users to upload files to the system.

Let’s understand it with an example.

In this example, you have to create two files and a folder to upload the attachments (like images, etc.). The two files are named index.php and upload.php, and the folder is named uploads.

Index.php contains the following programming code:

<form method="post" action="upload.php" enctype="multipart/form-data">  
    Attachment:  
    <br>
    <input type="file" name="myfile">  
    <br><br>
    <input type="submit" name="submit" value="Submit">  
</form> 

Upload.php contains the following programming code:

<?php  
 
$upload_path = "uploads/";  
$upload_path = $upload_path.basename( $_FILES['myfile']['name']);   
   
if(move_uploaded_file($_FILES['myfile']['tmp_name'], $upload_path)) {  
    echo "File uploaded successfully.";  
} else{  
    echo "An error occurred. Please try again.";  
}  
 
?>

Now run the index.php file.

Output:

• When the page loads:

• After uploading a file and submitting it:

If the file is successfully uploaded, it will generate a success message, as shown in the image below. Otherwise, an error message will be displayed. Visit the uploads folder that you have created to see the uploaded file.

Furthermore, PHP $_FILES are file upload variables. We can use the file_get_contents() function that reads a file into a string.

Frequently Asked Questions

Conclusion

PHP has several built-in functions for file manipulation. Commonly used file manipulation functions are PHP fopen(), fread(), fclose(), fwrite(), readfile() and unlink(). Furthermore, PHP allows users to upload files to the system.

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