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PHP Strings

A string is any finite sequence of characters (letters, numerals, symbols, punctuation marks, etc.)

PHP Strings Functions

PHP has a lot of string functions. Here we will learn about commonly used string functions with its usage.

PHP Strings - Output

The most popular function in PHP, echo is used to output a string.

PHP Output String Example

echo 'I am a string';
echo '<br>';

// multiple arguments
echo 'Hello', ' World', '!';

Run Example ››

Note: We have already discussed outputs in PHP in the PHP Output chapter. If you missed it, check it to learn more.

PHP Strings - Getting the Length

The strlen() function can be used to get the length of a string.

PHP Strings - Getting the Length Example

$str = 'Hyvor Developer';
echo strlen($str); // outputs 15

Run Example ››

PHP Strings - Number of Words

The str_word_count() function returns the number of words in a string.

PHP Strings - Number of Words Example

$str = 'This is a string with seven words';
echo str_word_count($str);

Run Example ››

PHP Strings - Changing The Case

The strtolower() and strtoupper() are used to make a string lowercase and uppercase respectively.

PHP Strings - Changing The Case Example

$str = 'Hyvor Developer';

echo strtolower($str); // hyvor developer
echo '<br>';
echo strtoupper($str); // HYVOR DEVELOPER

Run Example ››

PHP Strings - Removing Unnecessary Whitespace

The trim() function removes unnecessary whitespace from the beginning and the end of a string.

PHP Strings - Removing Unnecessary Whitespace Example

$str = '  Hyvor Developer    ';
echo strlen($str) . '<br>'; // length is 21

$str = trim($str); // remove whitespace
echo strlen($str); // now, length is 15

Run Example ››

Note: The trim() function is commonly used with PHP Forms.

PHP Strings - Reverse

The strrev() function is used to reverse a string.

PHP Strings - Reverse Example

$str = 'Hyvor Developer';
echo strrev($str);

Run Example ››

The strpos() function returns the position of the first occurrence of a substring in a string.

PHP Strings - Searching for a Substring Example

$str = 'Hello World';
echo strpos($str, 'World'); // will output 6

Run Example ››

Tip: In PHP, index of strings starts from 0. Therefore, the strpos() function returns 6 instead of 7 in the above example.

PHP Strings - Replacing Text within a String

The str_replace() function replaces a text within a string.

In this example, "Morning" in "Good Morning" will be changed to "Evening". The final result will be "Good Evening".

PHP Strings - Replacing Text within a String Example

$str = 'Good Morning';
echo str_replace('Morning', 'Evening', $str);

Run Example ››

PHP Strings - Repeating a String

The str_repeat() function is used to repeat a string number of times.

PHP Strings - Repeating Example

echo str_repeat('*', 20);

Run Example ››