phpmysql数据库连接类_PHP教程

class mysql {
private $db_host; //数据库主机
private $db_user; //数据库用户名
private $db_pwd; //数据库用户名密码
private $db_database; //数据库名
private $conn; //数据库连接标识;
private $result; //执行query命令的结果资源标识
private $sql; //sql执行语句
private $row; //返回的条目数
private $coding; //数据库编码，GBK,UTF8,gb2312
private $bulletin = true; //是否开启错误记录
private $show_error = true; //测试阶段，显示所有错误,具有安全隐患,默认关闭
private $is_error = false; //发现错误是否立即终止,默认true,建议不启用，因为当有问题时用户什么也看不到是很苦恼的

/*构造函数*/
public function __construct($db_host, $db_user, $db_pwd, $db_database, $conn, $coding) {
$this->db_host = $db_host;
$this->db_user = $db_user;
$this->db_pwd = $db_pwd;
$this->db_database = $db_database;
$this->conn = $conn;
$this->coding = $coding;
$this->connect();
}

/*数据库连接*/
public function connect() {
if ($this->conn == "pconn") {
//永久链接
$this->conn = mysql_pconnect($this->db_host, $this->db_user, $this->db_pwd);
} else {
//即使链接
$this->conn = mysql_connect($this->db_host, $this->db_user, $this->db_pwd);
}

if (!mysql_select_db($this->db_database, $this->conn)) {
if ($this->show_error) {
$this->show_error("数据库不可用：", $this->db_database);
}
}
mysql_query("SET NAMES $this->coding");
}

/*数据库执行语句，可执行查询添加修改删除等任何sql语句*/
public function query($sql) {
if ($sql == "") {
$this->show_error("SQL语句错误：", "SQL查询语句为空");
}
$this->sql = $sql;

$result = mysql_query($this->sql, $this->conn);

if (!$result) {
//调试中使用，sql语句出错时会自动打印出来
if ($this->show_error) {
$this->show_error("错误SQL语句：", $this->sql);
}
} else {
$this->result = $result;
}
return $this->result;
}

/*创建添加新的数据库*/
public function create_database($database_name) {
$database = $database_name;
$sqlDatabase = 'create database ' . $database;
$this->query($sqlDatabase);
}