PHP学习一

谁借莪１个温暖的怀抱￠ 2022-08-06 01:15 139阅读 0赞

<html>
    
    <head>
    	<title>Bob's Auto Parts-Order Results</title>
    </head>
    
    <body>
    	<h1>Bob's Auto Parts</h1>
    	<h2>Order Results</h2>
    
    	<p> Order Procesed.</p>
    
    </body>
    
    </html>

*  <html> 与 </html> 之间的文本描述网页
 *  <body> 与 </body> 之间的文本是可见的页面内容
 *  <h1> 与 </h1> 之间的文本被显示为标题
 *  <p> 与 </p> 之间的文本被显示为段落

<html>
    
    <head>
    	<title>Bob's Auto Parts-Order Results</title>
    </head>
    
    <body>
    	<h1>Bob's    Auto   
    	  Parts</h1>
    <h2>Order Results</h2>
    
    </body>
    
    
    <?php 
    	echo '<p> Order Procesed.';
    	echo date('H:i, jS F');
    	echo '</p>';
    ?>
    
    <?php
    	echo '<p> order procesed at ' . date('H:i,JS F') . '</p>';
    
    ?>
    
    </html>

<html>
    
    <head>
    	<title>Bob's Auto Parts-Order Results</title>
    </head>
    
    <body>
    	<h1>Bob's Auto Parts</h1>
    	<h2>Order Results</h2>
    
    </body>
    
    <?php
    	$tir = $_POST['tir'];
    	$oil = $_POST['oil'];
    
    	$tir = '1';
    	$oil = "a";
    
    	echo '<p> Your order is as follows: </p>';
    	echo $tir . 'tires <br>';
    	echo "$oil oil of<br>";	
    	//双引号中，变量名称被变量值所替代，单引号中变量名称或其他文本会不经修改发送给服务器
    ?>
    
    	
    </html>

<html>
    <head>
    	<title>Bob's Auto Parts-Order Results</title>
    </head>
    
    <body>
    
    <?php
    	Echo "hello world <br>";
    	echo "hello world <br>";
    	EcHo "hello world <br>";
    
    	$A = 1.1;
    	$a = 2;
    	echo "$A  $a";
    
    	//用户定义的函数，类，关键词（例如if else echo 等等）大小写不敏感，变量大小写敏感
    ?>
    
    
    
    </body>
    </html>

<html>
    <head>
    	<title>Bob's Auto Parts-Order Results</title>
    </head>
    
    <body>
    
    <?php
    	//类型转换
    	$total = 0;
    	$totalCnt = (float)$total;
    	echo "$total . $totalCnt <br>";
    
    	//变量
    	$x = 5;
    	$y = 2;
    	$z = $x + $y;
    	echo $z . '<br>';
    
    	//可变变量,起别名
    	$ref = total;
    	$$ref = 5.1;
    	echo "$total . $ref <br>";
    
    	//常量
    	define('MAX_APP_CNT',100);
    	$ref = MAX_APP_CNT;
    	echo MAX_APP_CNT . " $ref <br>";
    
    	//函数之外声明的只能在函数外访问，函数内声明的只能在函数内访问
    	function Test()
    	{
    		$a = 10;
    		echo "x is: $x <br>";
    	}
    	Test();
    	echo "a is: $a <br>";
    
    	//函数内访问函数外变量
    	function Test1()
    	{
    		global $x;
    		$x = 10;
    		echo "x is: $x <br>";
    	}
    	Test1();
    	echo "x is: $x <br>";
    
    	//PHP同时在名为$GLOBALS[index]的数组中存储了所有的全局变量
    	function Test2()
    	{
    		$GLOBALS['x'] = $GLOBALS['y'] + $GLOBALS['y'];
    	}
    	echo "x is: $x <br>";
    
    	//static 关键词
    	function Tes3()
    	{
    		static $x = 0;
    		echo "$x <br>";
    		$x ++;
    	}
    	Tes3();
    	Tes3();
    
    	//字符串运算符 . 
    	$y = $x . ' ab';
    	$y .= " $x";
    	echo "y is: $y <br>";
    
    	var_dump($x == $y);
    
    	//引用
    	$a = 5;
    	$b = $a;//产生副本
    	$c = &$a;
    	echo "$a . $b . $c <br>";
    
    
    ?>
    
    
    
    </body>
    </html>

echo 和 print 之间的差异：

*  echo - 能够输出一个以上的字符串
 *  print - 只能输出一个字符串，并始终返回 1

echo 比 print 稍快，因为它不返回任何值。

PHP var\_dump() 会返回变量的数据类型和值。

如需设置常量，请使用 define() 函数 - 它使用三个参数：

1.  首个参数定义常量的名称
2.  第二个参数定义常量的值
3.  可选的第三个参数规定常量名是否对大小写敏感。默认是 false。

<html>  
      
    <head>  
        <title>Bob's Auto Parts-Order Results</title>  
    </head>  
      
    <body>  
        <h1>Bob's    Auto     
          Parts</h1>  
    <h2>Order Results</h2>  
      
    </body>  
      
      
    <?php   
    /*	$fp = fopen("text.txt","ab+");
    	fwrite($fp, "hello");
    
    	$x = 1;
    	fwrite($fp, $x);
    	$fp = fopen("text.txt","rb+");
    	while (!feof($fp)) 
    	{
    		$order = fgets($fp,5); //指定长度减一
    		echo $order."<br>";
    	}
    	fclose($fp);
    
    
    
    	$stu = array("na","wang");
    	$stu["a"] = 1;
    	echo $stu[0] . ", " .$stu["a"] . ", " . count($stu) .".<br>";
    
    	$ss = array($stu,"hello");
    	echo $ss[0] . ", " .$ss[1] . ", " . count($ss) .".<br>";
    
    	foreach ($stu as $x => $x_value) {
    		echo "Key = " . $x . ", Val = " . $x_value . "<br>";
    	}
    
    	foreach ($ss[0] as $x => $x_value) {
    		echo "Key = " . $x . ", Val = " . $x_value . "<br>";
    	}
    
    */
    
    	require("tut1.php");
    ?>  
      
    
      
    </html>

<?php
    /*
    	//引用传参
    	function Test(&$val)
    	{
    		$val = 1;
    	}
    
    	$x = 2;
    	Test($x);
    	echo $x;
    
    */
    	
    	class ClassName
    	{
    		
    		function __construct()
    		{
    		}
    
    		public $name;
    	}
    
    	$a = new ClassName();
    	$a->name = "wang";
    	echo $a->name . "<br>";
    ?>

<?php
    	class A
    	{
    		protected function Test()
    		{
    			echo "hello <br>";
    		}
    		
    
    		public $name;
    	}
    
    
    	class B extends A
    	{
    		
    		function __construct()
    		{
    			A::Test();
    		}
    	}
    
    
    	$b = new B();
    	$b->name = "wang";
    	echo $b->name . "<br>";
    ?>