$_SERVER[‘REMOTE_ADDR’]

Header(‘location:index.php’);

$pattern = ‘/<script.*>.+</script>/’;Preg_replace($pattern,’’,$str);

$arr = array(‘’,1,2,3,’’,19);

$array1 = array('  ',1,'',2,3);print_r(array_filter($array1, "del"));function del($var){return(trim($var)); }

$arr=array("",1,2,3,"");$ptn="/S+/i";print_r(preg_grep($ptn,$arr));

Time();Date(“Y-m-d H:i:s”,Strtotime(“-1 day”));

Iconv(‘utf-8’,’gb2312’,$str);

$arr = explode(“,”,$str);

$arr = array(“测试1″,”测试2″,”测试3″);//数组$sarr = serialize($arr);//产生一个可存储的值(用于存储)

$unsarr=unserialize($newarr);//从已存储的表示中创建 PHP 的值

Function day_count($year,$month){Echo date(“t”,strtotime($year.”-”.$month.”-1”));}

$arr = pathinfo(“/wwwroot/include/page.class.php”);$str = substr($arr[‘basename’],strrpos($arr[‘basename’],’.’));

Class myclass{Public $aaa;Public $bbb;Public function myfun(){Echo “this is my function”;}}$myclass = new myclass();$myclass->$aaa;$myclass->myfun();

<?php$link = Mysql_connect(“localhost”,”root”,”123”) or die(“数据库连接失败!”);Mysql_select_db(“db_test”,$link) or die(“选择数据库失败!”);$sql = “select id,name,age,gender,phone,email from friend where age>20”;$result = mysql_query($sql);$count = mysql_num_rows($result);While($row = mysql_fetch_assoc($result)){Echo $row[‘id’];….}

1). mysql_query(“insert into user(name) values(‘test’)”);$id = mysql_insert_id();Mysql_query(“insert into score(uid,subjext,score) values(“.$id.”,’english’,’99’)”);2).$sql = select uid,sunjext,score from score where uid=2 order by score desc limit 0,5;3).select s.score from score s RIGHT JOIN user u ON u.id=s.uid where u.name=’张三;4).delete from score where uid in(select id from user where name=’李四’);Delete from user where name=’李四’;5).delete from score;6).drop table user;