In this PHP tutorial, you shall learn how to check if given string starts with an uppercase alphabet using preg_match() function, with example programs.
PHP Check if String Starts with Uppercase
To check if string starts with uppercase/capital letter, perform regular expression match if the first character is uppercase or not.
Provide the regular expression that a string starts with uppercase, and the string as argument to preg_match(). The function shall return true if the string starts with uppercase alphabet, or false if it does not.
Examples
1 Check if given string starts with an uppercase alphabet
In this example we will use preg_match() to perform a regular expression match.
The regular expression to check if the first character is uppercase alphabet or not, is
'~^\p{Lu}~u'
We will use this expressing with preg_match() built-in PHP function, to check if the string starts with uppercase. The syntax to use preg_match() for this use case is
preg_match('~^\p{Lu}~u', $string)
The above function call returns true if the string starts with uppercase alphabet, else it returns false.
In the following program, we will take a string “Hello World”, and check if this string starts with uppercase alphabet or not using preg_match().
PHP Program
<?php
$string = "Hello World!";
if ( preg_match('~^\p{Lu}~u', $string) ) {
echo "\"{$string}\" starts with uppercase.";
} else {
echo "\"{$string}\" does not start with uppercase.";
}
?>
Output
Conclusion
In this PHP Tutorial, we learned how to check if a string starts with an uppercase alphabet, using PHP built-in function preg_match().