How to delete text from file using preg_replace() function in PHP ? (original) (raw)

Last Updated : 14 Feb, 2020

Given a file containing some elements and the task is to delete the content of the file using preg_replace() function. The preg_replace() function is searches the string pattern in the file and if string pattern found then it replace with the required string. In simple words it can modify the contents of a file.Syntax:

preg_replace( pattern,pattern, pattern,replacement, $subject);

Parameters:

• $pattern: It contains the string we have to replace.
• $replacement: It contains the string that will replace the existing string.
• $subject: It contains the main string file where need to remove the string.

We have created a text file named as fruits.txt fruits.txt

mango apple papaya guava apple grapes mango apple

Program 1: This program removes all the strings from the given file.

php `

`

Output:

File contents before using preg_replace() function mango apple papaya guava apple grapes mango apple

File contents after using preg_replace() function

Program 2: This program deletes a specific content from the file using preg_replace() function.

php `

`

Output:

File contents before using preg_replace() function mango apple papaya guava apple grapes mango apple

File contents after using preg_replace() function mngo pple ppy guv pple grpes mngo pple

Program 3: This program deletes the entire word from the file.

php `

`

Output:

File contents before using preg_replace() function mango apple papaya guava apple grapes mango apple

File contents after using preg_replace() function mango papaya guava grapes mango