PHP File Open / Read / Close

PHP File Open / Read / Close

In PHP, file handling allows you to open, read, write, and close files stored on the server.
This is very important for logs, configuration files, data storage, and real-world applications.

 What is File Handling in PHP?

File handling in PHP means:

• Opening a file

• Reading data from it

• Writing data to it

• Closing the file

 PHP provides built-in functions for file handling.

 File Open – fopen()

Syntax

Common File Modes

Example: Open a File

 File Read – fread()

Syntax

Example: Read Entire File

 Reads full content of the file

Read File Line by Line – fgets()

 Very useful for large files

Read File Character by Character – fgetc()

File Close – fclose()

Syntax

Why Close a File?

•  Frees server memory
•  Prevents file corruption
• Good programming practice
•  Always close files after use.

 Shortcut Functions (Very Common)

file_get_contents()

Reads entire file in one line.

readfile()

Reads and outputs file directly.

 File Exists Check – file_exists()

 Avoids runtime errors

 Error Handling with Files

 Common Mistakes

•  Forgetting to close file
•  Using wrong file mode
•  Not checking file existence
•  Reading large files with fread()

Interview Questions & MCQs (Very Important)

Q1. Which function opens a file in PHP?

A) open()
B) file()
C) fopen()
D) read()

Answer: C

Q2. Which mode opens a file for reading only?

A) w
B) a
C) r
D) x

Answer: C

Q3. Which function reads a file line by line?

A) fread()
B) fgets()
C) fgetc()
D) readfile()

Answer: B

Q4. Which function closes a file?

A) close()
B) stop()
C) end()
D) fclose()

Answer: D

Q5. Which function reads entire file easily?

A) fread()
B) file_get_contents()
C) fgets()
D) fopen()

Answer: B

Q6. Why is fclose() important?

A) Speeds PHP
B) Frees memory
C) Prevents corruption
D) All of the above

Answer: D

 Real-Life Use Cases

•  Reading configuration files
•  Displaying text files
•  Logging user activity
•  File-based data storage

 Summary

• fopen() → open file

• fread(), fgets(), fgetc() → read file

• fclose() → close file

• Always check file existence

• Use shortcut functions for simplicity

• Very important for PHP exams & interviews