PHP function method knowledge

1. The strlen() function returns the length of the string in characters.

strlen returns the length of the string. strlen("hello") displays 5

2. The strpos() function is used to retrieve the specified characters or text within the string.

strpos("hello","e") displays 1 because it starts counting from 0.

3, Valid constant names start with a character or an underscore (there is no $ sign in front of the constant name).

Note: Unlike variables, constants are automatically global throughout the entire script.

4, count() function is used to return the length (number of elements) of the array. str is the string length.

The above has introduced the knowledge of PHP function methods, including aspects of the content. I hope it will be helpful to friends who are interested in PHP tutorials.