PHP循环之PHP基础入门教程

<?php
$i=1;
while($i<=5){
echo $i;
$i++;
}
?>

<?php
$i=6;
do
  {
  $i++;
  echo "The number is " . $i . "<br />";
  }
while ($i<5);
?>

<?php
for ($i=1; $i<=5; $i++)
{
  echo "Hello World!<br />";
}
?>

<?php
$arr=array("one", "two", "three");
foreach ($arr as $value)
{
  echo "Value: " . $value . "<br />";
}
?>

switch (expression)
{
case label1:
  code to be executed if expression = label1;
  break; 
case label2:
  code to be executed if expression = label2;
  break;
default:
  code to be executed
  if expression is different
  from both label1 and label2;
}

<?php
switch ($x)
{
case 1:
  echo "Number 1";
  break;
case 2:
  echo "Number 2";
  break;
case 3:
  echo "Number 3";
  break;
default:
  echo "No number between 1 and 3";
}
?>

</body>
</html>

$names = array("Peter","Quagmire","Joe");

$names[0] = "Peter";
$names[1] = "Quagmire";
$names[2] = "Joe";可以在脚本中使用这些 ID 键：

<?php

$names[0] = "Peter";
$names[1] = "Quagmire";
$names[2] = "Joe";

echo $names[1] . " and " . $names[2] . " are ". $names[0] . "'s neighbors";
?>

以上代码的输出：

Quagmire and Joe are Peter's neighbors

$ages = array("Peter"=>32, "Quagmire"=>30, "Joe"=>34);

<?php

$ages['Peter'] = "32";
$ages['Quagmire'] = "30";
$ages['Joe'] = "34";

echo "Peter is " . $ages['Peter'] . " years old.";
?>

以上脚本的输出：

Peter is 32 years old.

$families = array
(
  "Griffin"=>array
  (
  "Peter",
  "Lois",
  "Megan"
  ),
  "Quagmire"=>array
  (
  "Glenn"
  ),
  "Brown"=>array
  (
  "Cleveland",
  "Loretta",
  "Junior"
  )
);如果输出这个数组的话，应该类似这样：

Array
(
[Griffin] => Array
  (
  [0] => Peter
  [1] => Lois
  [2] => Megan
  )
[Quagmire] => Array
  (
  [0] => Glenn
  )
[Brown] => Array
  (
  [0] => Cleveland
  [1] => Loretta
  [2] => Junior
  )
)

echo "Is " . $families['Griffin'][2] .
" a part of the Griffin family?";

以上代码的输出：

Is Megan a part of the Griffin family?

$array1 = Array(
    0 => 111
);

$array2 = Array(
    0 => 222,
    1 => 3333
);

array_merge 后:
Array
(
    [0] => 111
    [1] => 222
    [2] => 3333
)

+ 后:
Array
(
    [0] => 111
    [1] => 3333
)

情况二:

$array1 = Array(
    0 => 111
);

$array2 = Array(
    'h' => 222,
    1 => 3333
);
array_merge 和 + 的结果是一样:
Array
(
    [0] => 111
    [h] => 222
    [1] => 3333
)

class A
{
    function A()
    {
      echo "I am the constructor of A.<br>n";
    }

    function B()
    {
        echo "I am a regular function named B in class A.<br>n";
        echo "I am not a constructor in A.<br>n";
    }
}

class B extends A
{
    function C()
    {
        echo "I am a regular function.<br>n";
    }
}

//php4 will call B()
$b = new B;

<?
/*
* 定义了 User接口.
* 和子类 NormalUser,VipUser,InnerUser
*/
//User接口,定义了三个抽象方法.
interface User{
 public function getName();
 public function setName($_name);
 public function getDiscount();
}
abstract class AbstractUser implements User{
 private $name = ""; //名字
 protected  $discount = 0; //折扣
 protected  $grade = "";  //级别
 
 public function __construct($_name){
  $this->setName($_name);
 }
 public function getName(){
  return $this->name;
 }
 public function setName($_name){
  $this->name = $_name;
 }
 public function getDiscount(){
  return $this->discount;
 }
 
 public function getGrade(){
  return $this->grade;
 }
}
class NormalUser extends AbstractUser  { 
 protected  $discount = 1.0;
 protected  $grade = "NormalUser";
}

class VipUser extends AbstractUser {
 protected  $discount = 0.8;
 protected  $grade = "VipUser";
}

class InnerUser extends AbstractUser {
 protected  $discount = 0.7;
 protected  $grade = "InnerUser";
}
?>

<?
/*与产品相关的类放.*/
Interface Product{ //定义产品接口
 public function getProductName();
 public function getProductPrice();
}

interface Book extends Product { // book是产品的一个分类
 public function getAuthor();
}

class BookOnline implements Book{ // 定义book类.
 private $productName;  // 产品名
 private $productPrice; // 产品价格
 private $author;  //作者
 
 public function __construct($_bookName){
  $this->productName = $_bookName;
  //这里放置相关初始化的代码.
  //与数据库关联的代码.
 }
 
 public function getProductName(){
  return $this->productName;
 }
 
 public function getProductPrice(){
  //这里从数据库读取价格.
  //假设价格是 100元.
  $this->productPrice = 100;
  return $this->productPrice;
 }
 
 public function getAuthor(){
  //从数据库里面取值.
  return $this->author;
 } 
}
?>

<?
include_once("User.php");
include_once("Product.php");
//买了产品到底多少钱呢?
class ProductSettle{
 public static function  finalPrice(User $_user,Product $_product,$number = 1){
  $price = $_user->getDiscount() * $_product->getProductPrice() * $number;
  return $price;
 }
}
?>

<?
include_once("./class/User.php");
include_once("./class/Product.php");
include_once("./class/ProductSettle.php");

$number = 10;
$book = new BookOnline("设计模式");

$user = new NormalUser("Tom");
$price = ProductSettle::finalPrice($user,$book,$number);
$str =  "您好，尊敬的用户 " . $user->getName() . " <br>";
$str .= "您的级别是 ". $user->getGrade() .", <br>";
$str .= "您的折扣是 " . $user->getDiscount() . "<br>";
$str .= "购买 $number 本 《 ". $book->getProductName() ;
$str .=  "》的价格是 $price <br><br>";
echo $str;

$user = new vipUser("Tom");
$price = ProductSettle::finalPrice($user,$book,$number);
$str =  "您好，尊敬的用户 " . $user->getName() . " <br>";
$str .= "您的级别是 ". $user->getGrade() .", <br>";
$str .= "您的折扣是 " . $user->getDiscount() . "<br>";
$str .= "购买 $number 本 《 ". $book->getProductName() ;
$str .=  "》的价格是 $price <br><br>";
echo $str;

$user = new InnerUser("Tom");
$price = ProductSettle::finalPrice($user,$book,$number);
$str =  "您好，尊敬的用户 " . $user->getName() . " <br>";
$str .= "您的级别是 ". $user->getGrade() .", <br>";
$str .= "您的折扣是 " . $user->getDiscount() . "<br>";
$str .= "购买 $number 本 《 ". $book->getProductName() ;
$str .=  "》的价格是 $price <br><br>";
echo $str;
?>