How to replace a URL to an Hyperlink in a String?

At times you come across a scenario where the string contains an http link and you need to create the hyperlink to the same.

This is can very well achieved using the single line of code.

$text = "This is http://www.phpcoaching.in site";
echo $text = ereg_replace("[[:alpha:]]+://[^<>[:space:]]+[[:alnum:]/]", "\\0", $text);

?>

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