The real power of PHP comes from its functions.

In PHP, more than 1000 built-in functions are provided.

For a complete reference manual and examples of all array functions, visit our PHP Reference manual.

In this chapter, we’ll show you how to create your own functions.

To execute a script when the page loads, you can put it in a function.

A function is executed by calling a function.

You can call functions from anywhere on the page.

Creating PHP functions Functions are performed by calling functions.

grammar

PHP function guidelines:

The function name should start with a letter or underscore (not a number). Example of a simple function that prints my name when called:

The instance

Output:

To add more functionality to a function, we can add parameters, which are like variables.

The parameters are specified in parentheses following the function name.

Example 1 The following instance will print a different name, but with the same last name:

The instance

Output:

My name is Kai Jim Refsnes. My sister’s name is Hege Refsnes. My brother’s name is Stale Refsnes. Example 2 The following function takes two arguments:

The instance

Output:

My name is Kai Jim Refsnes. My sister’s name is Hege Refsnes! My brother’s name is Stale Refsnes? To tell a function to return a value, use the return statement.

The instance

Output:

1 plus 16 is 17

Source code free download address: github.crmeb.net/u/defu