一、PHP基础语法 变量到数组
<?php
//phpinfo();
/* 变量
$a=1;//不分配空间
echo "\$a=".$a;
echo "<br/>";
var_dump($a);// 结果为NULL
echo "hello worrld";*/
/* int型最大能表示多大
echo "<br/>".PHP_INT_SIZE;
echo "<br/>".PHP_INT_MAX;//(2的31次方-1) 31：4*8-1个符号位
$a=-2147483648;
echo "<br/>".$a;
var_dump($a);//超过int型 范围 则会变为float类型*/
/* 布尔值
$d=0.0;
if(!$d){
echo "!!";
}*/
/* 浮点数
浮点数精度是14（从左边开始，第一个非0就是精度的开始）*/
/*字符型
单引号和双引号区别
$d=90;
$d1="$d";
$d2='$d';
echo $d1;
echo $d2;*/
//$a=7/5.1;
//echo $a;
# === 包括类型也相等
/*$a=2;
$b=2.0;
if($a!=$b)
{
echo"!=";
}
if($a!==$b)# !== 包括类型也不相等
{
echo "!==";
}*/
/* &&和||只要前面的一个为真假即不执行后一个
and 和 or 则不是
or的优先级比=低 所以
$e=false or true; //结果为false,因为此时$e先赋值为FALSE
var_dump($e);
$f=true and false;//结果为true,因为此时$e先赋值为true
var_dump($f);*/
/*字符串拼接
$a="1";$b="2";
$c=$a.$b;
*/
/* 对象类型运算符
class Dog{}
$dog=new Dog;
var_dump($dog instanceof Dog);
$a=3;
echo $a++*3;//9*/
/*常量
define("TAX_INT",21);
#$TAX_INT=9;
echo TAX_INT;
const TAX_TWO=0.3;
echo "<br/>".TAX_TWO; */
/*
#require 'other.php';//不会判断是否重复，可能导致重复输出
require_once 'other.php';// 先判断是否有重复引入
#include '111other.php';
#include_once 'other.php';
#require 和include区别：
#include如果出现了错误会继续执行，
#而require则会终止程序
#echo "22";
$i=2;
$result=getNum($i);//传值，也可以传地址&
echo $result;*/
/*全局变量 global
$a=1;
function get()
{
global $a;//可作用于局部内了
$a++;
}
get();
echo $a;
*/
/*数组初始化
//$array=array(1.2,12,"wrwe",true);
//echo count($array);
$arr=array("log"=>"daomul","mima"=>123);
echo count($arr)."<br/>";
foreach($arr as $key=>$val)
{
echo $key."=".$val."<br/>";
}
$arr2=array(""=>"32",1=>"fdsf",23,23);
echo $arr2[""]."<br/>";
echo $arr2[2]."<br/>";
#使用true作为下标，即是1 ,false :0; null:""
$arr3=array(123.4=>"arr3");
echo $arr3[123]."<br/>";
#显示详细数组信息
print_r($arr3); echo "<br/>";
var_dump($arr3);
#数组可以动态增长
$arr4=array(2,3);
echo $arr4[1]."<br/>";
$arr4[2]='11 22 333 444';
#echo $arr4[2];
#字符串的拆分 explode
$arr=explode(" ",$arr4[2]);
print_r($arr);
foreach($arr as $key=>$val)# (要循环的数组 as 数组下标变量)
{
echo "<br/>$key=>$val";
}
echo "<br/>".$arr[1];
unset($arr[1]);#销毁数组元素后，关键字下标不会被重新填充组合
print_r($arr);*/
/*数组运算 叠加
$a=array("a"=>12,"b"=>23);
$b=array("a"=>21,"c"=>43);
$a=$a+$b;
print_r($a);*/
?>二、数组
<html>
<head>
<meta http-equiv="content-type" content="text/html;charset=utf-8">
</head>
<body>
<h1 id="nbsp-同一个界面传输参数"> 同一个界面传输参数</h1>
<?php
/* 在 input中加 value="<?php echo $grades; ?>" 仿造百度搜索 */
error_reporting(E_ALL ^ E_NOTICE);
$grades=$_REQUEST['grade'];
$grade=explode(" ",$grades);
$all=0;
foreach($grade as $k=>$v)
{
$all+=$v;
}
?>
<form action="test.php" method="post">
<input type="text" name="grade" value="<?php echo $grades; ?>"/>
<input type="submit" value="start"/>
</form>
<?php
echo "总的：".$all;
?>
</body>
</html>三、静态变量
<?php
class Child
{
public static $num=0;
public $name;
function __construct($name) //只有new之后才能调用
{
$this->name=$name;
}
//静态变量不能用this来访问
public function join()
{
self::$num+=1; //可以： Child::$num
echo $this->name."you";
}
}
$child1=new Child("k");
$child1->join();
$child1=new Child("a");
$child1->join();
$child1=new Child("b");
$child1->join();
echo "<br/>".Child::$num;
//类外只能是 类名：：变量，
//类内就能两种
?>四、继承/封装/多态/抽象
/*class Child
{
public static $num=0;
public $name;
//构造方法
function __construct($name) //只有new之后才能调用
{
$this->name=$name;
}
//静态变量不能用this来访问
public function join($ifee)
{
self::ifee+=1; //可以： Child::$num
echo $this->name."you";
}
}
$child1=new Child("k");
$child1->join();
$child1=new Child("a");
$child1->join();
$child1=new Child("b");
$child1->join();
echo "<br/>".Child::$num;
//类外只能是 类名：：变量，
//类内就能两种*/
//静态方法不能采用非静态变量，只能使用非静态变量
// 成员函数之间相互调用，需要用 $this->text();
//继承
//1、子类只能继承一个父类
// 如果想多重继承可以考虑通过多次继承：
/*class A{}
class B extends A{}
class C extends B{}*/
//2、父类中的构造方法，在创造一个子类的对象实例的时候不会默认自动调用
//3、 子类中调用父类的方法
//父类名::方法名(); / parent::方法名(); parent小写的
//覆盖：
# 子类的方法和父类的方法名称和参数个数完全一样，但不要求参数名相同
# 但是修饰符可以不同，但是子的范围〉=父类范围
# 父类是private则不能覆盖
/*class A{
function F(){
echo " 父类在此！<br/>";
}
}
class B extends A{}
class C extends B{
function F(){
echo "调用了父类了<br/>";
parent::F();
A::F();
}
}
$C1=new C();
$C1->F();*/
//抽象类：父类中不需要被实例化，只让子类继承，也可以被调用里面的；达到代码复用
#抽象类 abstract class name{}
#抽象方法 abstract public cry();
#抽象类不一定也有抽象方法
#类包含抽象方法则必须为抽象类
#子类继承抽象父类，则必须为抽象类或者实现继承的所有，所有！方法
//接口：interfacde 接口{//属性 //方法}
# 只能定义规范，让类去实现接口 ，不能自己实现，
# class c implements 接口{}
# 接口不能被实例化/接口能继承其他多个接口/不能不为public
# 一个类实现了一个接口，必须把接口以及其继承的接口的方法全部实现
# (1 多个平级的类都要实现某个功能，只是实现方式不同，没有继承关系，
#（2 项目经理定规范，让其他程序员实现
/*interface Stu
{
const A=90;
public function add();
}
interface Stu2{}
class MyStu implements Stu,Stu2
{
public function add()
{
echo "dddd".Stu::A."<br/>";
}
}
$mystu=new MyStu();
$mystu->add();
echo "OK".Stu::A; #获得接口中的常量*/
//final 使类中的方法不被覆盖
# final 不能修饰成员属性
/*class A
{
final public function get($salary)
{
return $salary*3;
}
}
class B extends A
{
public function get($sal)
{
return $sal*2;
}
}
$b=new B();
$b->get("21"); #Cannot override final method A::get() */
//const常量
# 要赋初始值；不能后面赋值；不能加$等修饰符
# self::A ; 类名::A ;接口名::A; 等方式获得常量A的值五、文件操作以及错误处理
<?php
// 文件操作
/*处理错的方式1
if(!file_exists("file1.txt"))
{
echo "not here";
exit();
}
else
{
$fp=fopen("file1.txt","r");
echo "文件已打开";
fclose($fp);
}*/
/* 处理错的方式2
if(!file_exists("a.txt"))
{
die("wenjianbucunzai");
}
else
{}
echo "end";*/
/*处理错的方式1
file_exists("b.txt") or die("zhen de ");
echo "end";
*/
//定义错误函数
/*function my_error($error,$err_message)
{
echo "<font size='5' color='red'> $error </front><br/>";//2
//echo "错误信息是：".$err_message;
exit();
}
//改变系统默认的错误处理函数（“用户自己定义的错误输出函数”，“错误类型”）
set_error_handler("my_error",E_WARNING);
$fp=fopen("aa.txt",'r');*/
//错误触发器
function my_error3($error,$err_message)
{
echo "错误号：".$error;
}
function my_error4($error,$err_message)
{
echo "big big!";
}
set_error_handler("my_error3",E_USER_WARNING);//
set_error_handler("my_error4",E_USER_ERROR);//致命错误，不继续执行
$age=140;
if($age>120)
{
//调用触发器的时候指定错误级别
trigger_error("输入的数字过大！",E_USER_ERROR);
//trigger_error("输入的数字过大！",E_USER_WARNING);
//exit();
}
echo "ok";
?>六、错误日志
<?php
//错误日志 php.ini 中的error_log的配置
function my_error5($error,$err_meaasge)
{
$err_info="错误信息：".$error."--".$err_meaasge;
//echo time();
//输出 当前日期
// 调整时区：默认时期是UTC和中国差8小时 PRC 或者Asia/Chongqing
date_default_timezone_set("PRC");
echo date("Y-m-d G-i-s");
echo "<br/>".$err_info;
#将错误存入系统文件中
error_log("时间是：".date("Y-m-d G-i-s")."-".$err_info."\r\n",3,"myerror.txt");//3个参数
}
set_error_handler("my_error5",E_USER_WARNING);
$i=1;
if($i<2)
{
trigger_error("输入的数字过小",E_USER_WARNING);
}
?>七、捕获异常
<?php
//处理异常
#注意事项：异常抛出之后，得代码不会被继续执行
#抛出异常之后如果没用处理则会报错
try
{
addUser("1a");
}
catch(Exception $e)
{
echo "失败信息：".$e->getMessage();//getLine()
#可以继续抛出 throw $e;
#也可以顶一个顶级异常处理
# $i=8/0 fopen("a.txt","r") 很难抛出异常
}
function addUser($user)
{
if($user=="a")
{
echo "登陆成功！";
}
else
{
throw new Exception("用户名错误!");
}
}
/*#顶级异常处理
function my_error()
{
echo "我是顶级异常处理！".e->getMeaasge();
}
set_error_handler("my_error");*/
?>
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