数据库连接练习

<?php
//链接sql
class db{
    //基本类
    public $con;
    public static $sname="127.0.0.1";
    public static $uname="root";
    public static $pword="";
    
    //静态变量
public function __construct(){
    //构造函数先执行 不能为静态
    $this->con = mysql_connect(self::$sname,self::$uname,self::$pword);
if(!$this->con){
    die("cound no connect:".mysql_error());
}
}
public function o($sql){
    mysql_select_db("L_db",$this->con);
    mysql_query($sql,$this->con);
}
function __destruct(){
    //这是个析构函数， 在对象销毁前调用
    mysql_close($this->con);
}
}
class cr extends db {
    //派生 创建类
    function create(){
//创建 database
if (mysql_query("CREATE DATABASE L_db",$this->con)){
    echo "Database created";
}else{
    echo "Error creating database".mysql_error();
}
}
function create_tabe(){
    //创建表
mysql_select_db("L_db", $this->con);
    //选着数据库
$sql = "CREATE TABLE PCR(
FilstName varchar(15),
LastName varchar(16),
Age int
)";
mysql_query($sql,$this->con);
}
}
class rw extends db {
    function w($f,$l,$a){
        $sql="INSERT INTO PCF(FilstName,LastName,Age)
        VALUES(
        ‘$f‘,‘$l‘,‘$a‘)";
        db::o($sql);
    }
    function rall (){
        $sql="SELECT * FROM PCF";
        var_dump(db::o($sql));
        $sql=db::o($sql);
        while($row=mysql_fetch_array($sql)){
            echo $row[‘FilstName‘]." ".$row[‘LastName‘];
            echo "<br />";
        }
    }
}


$f=@$_POST[‘firstname‘];
$l=@$_POST[‘lastname‘];
$a=@$_POST[‘age‘];
var_dump($a,$l,$f);
$rw=new rw();
$rw->w($f,$l,$a); 
$rw->rall();



//创建数据库
//$cdb=new cr;
//$cdb->created(); 创建数据库
//$cdb->create_tabe(); //创建数据表
//PCRID int NOT NULL AUTO_INCREMENT,
//PCRID 不能为空 设置为自动增加
//PRIMARY KEY(PCRID),
//FilstName varchar(15),
//varchar 类型 （15）最大长度
$sql1="CREATE TABLE PCM(
PCRID int NOT NULL AUTO_INCREMENT,
PRIMARY KEY(PCRID),
FilstName varchar(15),
LastName varchar(15),
Age int
)";
$sql2="CREATE TABLE PCF(
PCRID int NOT NULL AUTO_INCREMENT,
PRIMARY KEY(PCRID),
FilstName varchar(15),
LastName varchar(15),
Age int
)";
$sql3="INSERT INTO PCF(
FilstName,LastName,Age)
VALUES (‘Glenn‘,‘Query‘,‘33‘)";
//$srw=new srw;
//$srw->w($sql3);

//db::o($sql2);
?>