PHP基本语法学习
<?php
echo 'hello<br>';
//phpinfo();
echo date('Y-m-d');
$func = true;
var_dump($func);
$int = 5;
echo 'hello' . gettype($func) . '<br>' . $int;
if (is_array($int)) {
echo 'is array';
} else {
echo 'is not array';
}
$i = 1.111112;
$ii = 3.14;
echo $i . ',' . gettype($i);
echo '<br>
break usage
what do you like?
';
echo '<br> \print'danyinh'<br>';
echo "abc$i${ii}i<br>";
$str = <<<EOF
hello eof
are you ok?$i<br>'dkdk'
EOF;
echo "strange string output $str <br>";
//serialize($str);
$arr = ['a' => 'b', 'c', 'b', 'c' => 'd', 'c'];
echo $arr['a'] . '<br>';
var_dump($arr);
echo $arr[0] . '<br>';
class foo {
function printLog() {
echo "log print <br>";
}
}
$f = new foo;
$f->printLog();
$obj = (object)'hello sang';
var_dump($obj);
$var_arr = get_object_vars($obj);
foreach ($var_arr as $k => $v) {
echo "$k:$v<br>";
}
echo '$obj class is :' . get_class($obj) . '<br>';
$obj_from_arr = (object)$arr;
var_dump($obj_from_arr);
//---- 传值＆传引用 ------//
$var1 = 'abc';
$var2 = 12;
echo "var1:$var1" . ",var2:$var2<br>";
$var3 = $var1;
echo "var3:$var3";
$var1 = 'ab';
echo ",by_value_var3:$var3";
$var3 = &$var1;
echo ",by_ref_var3:$var3";
//---------- 预定义变量 ------
var_dump($GLOBALS);
//---- 表单提交例子 ---------
var_dump($_POST);
?>
<html>
<body>
<form action="<?php $_SERVER['PHP_SELF']; ?>" method="post">
<input type="text" name="uname"/>
<input type="submit" name="submit" value="save"/>
</form>
</body>
</html>
<?php
//---------- 常量 -----------
define("TEST_MAIN", 'hello');
echo TEST_MAIN;
echo 'current file path : ' . __FILE__;
//--------- 数组运算符------------
$arr1 = array('1' => 'abc', '2' => 'def');
$arr2 = array('1' => '123', '3' => '456');
var_dump($arr1 + $arr2);
//-------- instanceof ---
class A {
}
class B {
}
$a = new A;
echo $a instanceof A;
//------- 反引号----------------------
$list = ls -alh ./;
echo $list;
//--- foreach遍历
foreach ($arr1 as $k => $v) {
echo $k . ':' . $v . '<br>';
}
foreach ($arr1 as $v) {
echo $v;
}
foreach ($arr1 as &$v) {//加上＆修改数组原值
$v = '111';
}
var_dump($arr1);
//-------------- 范围解析符（静态调用） ---------------------
class Test {
function printMsg($msg) {//默认是public的
echo $msg;
}
}
$msg = 'hello world';
Test::printMsg($msg);
// ---------- 静态属性 静态方法 -----------------
class TestA {
static $name = 'abc';
function showName() {
echo self::$name; //方法内部调用
}
}
class TestB {
var $name = 'abc';//必须带上修饰符比如 var, public,private,protected
function showName() {
echo $this->name;
}
}
class TestC {
const MAXSIZE = 12;//类里定义常量
static $mtd = 'ad';
var $mtd2 = 'abc';
static function showMtd() {
echo 'static method:' + self::$mtd;
}
function showMtd2() {
echo 'normal method:' + $this->mtd;
}
function getConst() {
echo self::MAXSIZE;
}
}
TestC::showMtd();
//TestC::showMtd2();//此时this会报错,无法找到.和java还是区别很大
$tc = new TestC();
echo TestC::MAXSIZE;//访问类中常量
// -------------- 类的继承 -----------------------
class Pa {
var $a = 'you ok?';
function show() {
echo 'from parent;';
}
}
class Ch extends Pa {
function show() {
echo 'from child;';
//也指明再执行父亲方法
parent::show();
}
}
$ch = new Ch;
echo $ch->a;
$p = new Pa;
$c = new Ch;
$p->show();
$c->show();
//------------ 构造函数 －－－－－－－－－－－－－－
class T1 {
function __construct() {
echo 'abcdddd;';
}
}
class T2 extends T1 {
function __construct() { //不带参数构造函数，基类自动执行
echo 'ddddddd;';
}
}
$t2 = new T2;
class T3 {
var $a;
function __construct($a) {
$this->a = $a;
}
}
class T4 extends T3 {
function __construct($a) {
parent::__construct($a);//父子类构造函数带参，则必须显式调用父类构造函数！
}
}
//------------------- 析构函数 －－－－－－－－
class T5 {
var $a;// php4中用var,php5用public,但兼容var,参考http://www.kuitao8.com/20150427/3717.shtml
function __destruct() {
echo ou'do destruct;';
}
}
$t5 = new T5;
unset($t5);
// ------------------ 序列化＆反序列化 －－－－－－－－－－－－－－－－－－－－－
class T6{
public $a;
public $b;
function __sleep() {
return(array('a'));//只序列化ａ
}
function __wakeup() {
$this->b = uniqid();//初始化未序列化的b
}
}
$t6 = new T6;
$t6->a = 'sang;';
$t6s = serialize($t6);
$t6us = unserialize($t6s);
var_dump($t6us);
// ------------------- 字符串操作 --------------------
$str1 = 'abcdefgHIGK ';
echo $str1{0};
echo strlen($str1);
echo strlen(trim($str1));
echo strtoupper($str1);
echo strcmp($str1,$str);
echo substr($str1,0,2);//ab
echo substr_replace($str1,'11',0,2);
echo substr_replace($str1,'11',-1,-2);
echo strpos($str1,'e');
$str2 = 'a|b|c';
$str_arr = explode('|',$str2);//分割
var_dump($str_arr);
$str3 = implode('@',$str_arr);//合并
echo $str3;
$str4 = 'http://blog.csdn.net/spy19881201/article/details/25537225?a=1&;b=2';
var_dump(parse_url($str4));
// ----------- 正则表达式 －－－－－－－－－－－－－－
echo preg_match('/^a?b$/','ab');
echo preg_match('/^a?b$/','aab');
echo preg_match('/^-{0,1}[0-9]{0,}.{0,1}[0-9]{0,}$/','-1.2');
echo preg_match('/^-?[0-9].?[0-9]$/','-1.2');
//--------------------- 数组 -------------------------
$arr1 = array('a','b');//索引数组
$arr2 = array('1'=>'a','2'=>'b');//关联数组
var_dump($arr1);
var_dump($arr2);
$arr3 = array('a','1'=>'b','0' =>'c');//注意，如果key为整形字符串，比如'0'，会转成索引数组．数组后面的值覆盖前面的值
var_dump($arr3);
echo $arr3['0'];
$arr4['a'] = 'b';//arr4不存在，则自动创建一个！！！
foreach ($arr2 as $item){
echo $item;
}
foreach ($arr2 as $k => $v){
echo $k.':'.$v;
}
phpinfo();
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