PHP functions consist of a name, parameter list, function body, return type (optional) and visibility modifier (optional). For example, the greetUser($name) function accepts a name parameter and displays a welcome message.
Deconstruct the components of PHP function
PHP function consists of the following parts:
1. Function name
This is the unique identifier of the function, which determines how the function is called.
2. Parameter list
The parameter list specifies the data passed to the function. The parameter list contains zero or more parameters separated by commas. Each parameter has a type and a variable name.
3. Function body
The function body contains the code to be executed. It is enclosed in curly brackets ({}
).
Practical case:
The following is a PHP function named greetUser()
, which accepts a username and displays a welcome message Text of:
function greetUser($name) { echo "欢迎来到网站,$name!"; }
In this function:
-
greetUser()
is the function name. -
($name)
is a parameter list that accepts a string parameter named$name
. -
echo "Welcome to the website, $name!"
; is the function body, which outputs a welcome message containing the user name.
4. Return type
Optional. The return type specifies the type of value returned by the function. If omitted, the function returns void
.
5. Visibility modifier
Optional. Visibility modifiers specify whether a function is accessible from other scopes. The default visibility is public
.
Example:
// 公共函数 public function publicFunction() { // ... } // 私有函数 private function privateFunction() { // ... }
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