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<?php$db = array（"host"=>"localhost","user"=>"root","password"=>"","database"=>"test",）?>

<?phpclass db {public $conn;public static $sql;public static $instance=null;private function __construct（）{require_once（"db.config.php"）;$this->conn = mysql_connect（$db["host"],$db["user"],$db["password"]）;if（！mysql_select_db（$db["database"],$this->conn））{echo "失败";};mysql_query（"set names utf8",$this->conn）;}public static function getInstance（）{if（is_null（self::$instance））{self::$instance = new db;}return self::$instance;}/** * 查询数据库 */public function select（$table,$condition=array（）,$field = array（））{$where="";if（！empty（$condition））{foreach（$condition as $k=>$v）{$where.=$k."="".$v."" and ";}$where="where ".$where ."1=1";}$fieldstr = "";if（！empty（$field））{foreach（$field as $k=>$v）{$fieldstr.= $v.",";} $fieldstr = rtrim（$fieldstr,","）;}else{$fieldstr = "*";}self::$sql = "select {$fieldstr} from {$table} {$where}";$result=mysql_query（self::$sql,$this->conn）;$resuleRow = array（）;$i = 0;while（$row=mysql_fetch_assoc（$result））{foreach（$row as $k=>$v）{$resuleRow[$i][$k] = $v;}$i++;}return $resuleRow;}/** * 添加一条记录 */ public function insert（$table,$data）{$values = "";$datas = "";foreach（$data as $k=>$v）{$values.=$k.",";$datas.=""$v"".",";}$values = rtrim（$values,","）;$datas= rtrim（$datas,","）;self::$sql = "INSERT INTO {$table} （{$values}） VALUES （{$datas}）";if（mysql_query（self::$sql））{return mysql_insert_id（）;}else{return false;}; } /** * 修改一条记录 */public function update（$table,$data,$condition=array（））{$where="";if（！empty（$condition））{foreach（$condition as $k=>$v）{$where.=$k."="".$v."" and ";}$where="where ".$where ."1=1";}$updatastr = "";if（！empty（$data））{foreach（$data as $k=>$v）{$updatastr.= $k."="".$v."",";}$updatastr = "set ".rtrim（$updatastr,","）;}self::$sql = "update {$table} {$updatastr} {$where}";return mysql_query（self::$sql）;}/** * 删除记录 */ public function delete（$table,$condition）{$where="";if（！empty（$condition））{foreach（$condition as $k=>$v）{$where.=$k."="".$v."" and ";}$where="where ".$where ."1=1";}self::$sql = "delete from {$table} {$where}";return mysql_query（self::$sql）; }public static function getLastSql（）{echo self::$sql;}}$db = db::getInstance（）;//$list = $db->select（"demo",array（"name"=>"tom","password"=>"ds"）,array（"name","password"））;//echo $db->insert（"demo",array（"name"=>"脚本之家","password"=>"123"））;//echo $db->update（"demo",array（"name"=>"xxx","password"=>"123"）,array（"id"=>1））;echo $db->delete（"demo",array（"id"=>"2"））;db::getLastSql（）;echo "<pre>";?>