24 Nov 09 PHP Programmer – strlen, count and substr

PHP Developer – strlen, count, and substr

The strlen function retuns the length, i.e. number of characters in a string:  int strlen(string s)

count will get the number of elements in an array:  int count(array a)

substr will return a “subset” of a string, string substr(string s, int start, [int len]);
<?php
$s = “test string”;
echo “String length is: ” . strlen($s);
?>

Will return:  String length is: 11

Why would you care how long a string is? Well, for many reasons, one being that you might wish to iterate through each character of a string to perform a certain conditional check or operation on each character. Alternatively, you might want to check that a certain string is not over a given size, and if so, shorten it. Here’s a common example that shows these three common functions together:

<?php
$myarray = Array("This is a very long string", "short string", "some text", "some more text to be shortened");
define(MAXLEN, 20); //maximum permitted string length
$num = count($myarray); //Get the number of elements in the array
for ($ctr = 0; $ctr < $num; $ctr++)
{
    if (strlen($myarray[$ctr]) > MAXLEN)
    {
        echo substr($myarray[$ctr], 0, (MAXLEN - 3)) . "...\n";
    } else {
        echo $myarray[$ctr] . "\n";
    }
}
?>

The above will output:
This is a very lo…
short string
some text
some more text to…

This could be used in an instance where we only want to show a predefined “taster”, i.e. replacing … with “(more)” or similar. Alternatively, ensuring that text does not overflow a “<div>” element in a particular instance

Tags: count, PHP, php programmer, strlen, substr

Leave a Comment

You must be logged in to post a comment.