PHP

Extracting Substrings

You want to extract part of a string, starting at a particular place in the string. For example, you want the first eight characters of a username entered into a form.

Use substr($string, $start, $length) to select your substring. If $start and $length are positive, substr() returns $length characters in the string, starting at $start. The first character in the string is at position 0.

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="EN" lang="EN">
<head>
<title>PHP</title>
<meta Name="Author" Content="Hann So">
</head>
<body>
<p>
<?php
$username = 'John Doe';
echo "Extract $username with start=5: ", substr($username, 5),
"<br />";
echo "Extract $username with start=2 and length=4: ", substr($username, 2, 4),
"<br />";
echo "Extract $username with start=20: ", substr($username, 20),
"</br />";
echo "Extract $username with start=5 and length=5: ", substr($username, 5, 5),
"<br />";
echo "Extract $username with start=-5: ", substr($username, -5),
"<br />";
echo "Extract $username with start=-5 and length=5: ", substr($username, -5, 5),
"</r />";
echo "Extract $username with start=-10: ", substr($username, -10),
"<br />";
echo "Extract $username with start=5 and length=-5: ", substr($username, 5, -5),
"<br />";
echo "Extract $username with start=-5 and length=-5: ", substr($username, -5, -5),
"<br />";
?>
</p>
</body>
</html>

View the effect