// execute this if no break statement
// has been encountered hitherto
}
3) ?操作符:
( expression )?returned_if_expression_is_true:returned_if_expression_is_false;
4) while 语句:
(1
) while ( expression )
{
// do something
}
(2)do
{
// code to be executed
} while ( expression );
5) for 语句:
for ( initialization expression; test expression; modification expression ) {
// code to be executed
}
6) break;continue
9
、
编写函数
1) 定义函数:
function function_name($argument1,$argument2,……) //形参
{
//function code here;
}
2) 函数调用
function_name($argument1,$argument2,……); //形参
3) 动态函数调用(Dynamic Function Calls):
<html>
<head>
<title>Listing 6.5</title>
</head>
<body>
<?php
function sayHello() { //定义函数 sayHello
print "hello<br>";
}
$function_holder = "sayHello"; //将函数名赋值给变量$function_holder
$function_holder(); //变量$function_holder 成为函数 sayHello 的引用,调用
$function_holder()相当于调用 sayHello
?>
</body>
</html>
4) 变量作用域:
全局变量:
<html>
<head>
<title>Listing 6.8</title>
</head>
<body>
<?php
$life=42;
function meaningOfLife() {
global $life;
/*在此处重新声明$life 为全局变量,在函数内部访问全局变量必须这样,如果在函数内改变变量的值,
将在所有代码片段改变*/
print "The meaning of life is $life<br>";
}
meaningOfLife();
?>
</body>
</html>