How does Perl calculate the length of a string?

In Perl, you can use the length() function to calculate the length of a string. Here is an example:

my $string = "Hello, world!";
my $length = length($string);
print "字符串的长度为：$length\n";

Running the above code will output:

字符串的长度为：13

In this example, we have defined a string variable $string and used the length() function to calculate its length. Then, we printed out the result.