There are following steps involve in File manipulation :

1. Open the file for read or write.
2. Read the file.
3. Close the file.
4. Perform operations on the file content.
5. Print the result.

Modes	Description
r	Read only at the beginning of the file.
r+	Read or Write at the beginning of the file
w	It will create a new file if it does not exist and if exist it erase the contents of any file of this name before writing.
w+	Read and Write if the file doesn't exist so it will create a file of this name, and if exist it will erase the contents of any file of this name before writing.
a	Append,use to open and write to the end of the file if exist.
a+	Read and Write to the end of the file if exist.

Open the file

fopen() : This function is used to open the files in PHP.

Example :

<?php
$file=fopen("D:\tkhts\id.txt","r")
 
or exit("Unable to open file!");
?>

Closing the File

fclose() :This function is used to close an open file.

Example :

<?php
$file = fopen("D:\tkhts\id.txt","r");

//code executed

fclose($file);
?>

End-of-file

feof :This function checks end-of-file on a file pointer and takes a filename as argument and it is used in a while loop to perform the same task(function) on each line in a file.

Syntax :

while(!feof($f))
  {
$val=fgets($f);
echo "val";
echo"end of file";
  }
  

Read the file

fgets() :This function is used to read a single line from a file in PHP. fgetc() :This function is used to read a single character from a file.

Example1 :

<?php
$f = fopen("D:\tkhts\id.txt", "r") 

or exit("Unable to open file!");

while(!feof($f))
  {
  echo fgets($f). "<br>";
  }
fclose($f);
?>

Output :

Learn PHP from : 

www.tkhts.com 

Example 2:

<?php
$file=fopen("D:\tkhts\id.txt","r") 

or exit("Unable to open file!");

while (!feof($f))
  {
  echo fgetc($f)."<br>";
  }
fclose($f);
?>

Output :

L
e
a
r
n

P
H
P

f
r
o
m

:


w
w
w
.
t
k
h
t
s
.
c
o
m