class DB
{
static $link=null; //mysql服务器连接的资源
private $host=""; //mysql服务器主机名
private $user=""; //mysql的用户名
private $password=""; //mysql的密码
private $db=""; //访问的数据库名
//构造方法
function __construct($db='',$host="127.0.0.1",$user="root",$password=''){
$this->host=$host;
$this->user=$user;
$this->password=$password;
$this->db=$db;
if(self::$link==null)
{
self::$link=mysql_connect($this->host, $this->user,$this->password);
mysql_select_db($this->db,self::$link);
$this->query('SET NAMES utf8');
}
}
function selectDb($db){
return mysql_select_db($db) or die('选择数据库失败'.mysql_error());
}
function getRow($sqlStr,$result_type=MYSQL_ASSOC)
{
$rs=@mysql_query($sqlStr,self::$link) or $this->showError("查询语句有错误！$sqlStr");
if($rs)
{
$row=@mysql_fetch_array($rs,$result_type);
return $row;
}
return false;
}
function getAll($sql,$result_type=MYSQL_ASSOC)
{
$rs=@mysql_query($sql,self::$link) or $this->showError("查询语句有错误！$sql");
if($rs===false)
{
return false;
}
else if($rs===true){
return true;
}
else{
$arr=array();
while($row=@mysql_fetch_array($rs,$result_type))
{
$arr[]=$row;
}
return $arr;
}
}
function getObjects($sql){
$rs=mysql_query($sql,self::$link) or $this->showError("查询语句有错误！");
if($rs===false){
return false;
}
$arr=array();
while($row=@mysql_fetch_object($rs)){
$arr[]=$row;
}
return $arr;
}
function query($sql)
{
$bl = mysql_query($sql,self::$link) or $this->showError();
return $bl;
}
function showError($error="")
{
echo $error;
echo '
';
echo mysql_error();
echo '
';
}
function insert($table,$dataArray){
$fields="";
$values="";
if(!is_array($dataArray) || count($dataArray)<=0) {
$this->showError('没有要插入的数据');
return false;
}
$fields=implode(',',array_keys($dataArray));
$values=implode("','",array_values($dataArray));
$values="'".$values."'";
$sql = "insert into $table($fields) values($values)";
return mysql_query($sql) or $this->showError("插入语句有错误！$sql");
}
public function update($table,$dataArray,$condition="1=1") {
if( !is_array($dataArray) || count($dataArray)<=0) {
$this->showError('没有要更新的数据');
return false;
}
$value = "";
$field = "";
foreach($dataArray as $key=>$val) {
$value .="$key = '$val',";
}
$value = substr( $value,0,-1);
$sql = "update $table set $value where $condition";
return mysql_query($sql) or $this->showError("更新语句有错误！$sql");
}
public function delete($table,$condition="") {
if(empty($condition)) {
$sql="delete from $table";
}
else if(is_string($condition)){
$sql="delete from $table where $condition";
}
return mysql_query($sql) or $this->showError("删除语句有错误！$sql");
}
function closeDb()
{
mysql_close(self::$link);
}
}
?>
使用:
//添加
include("./db.class.php");
$db=new DB("db");
$arr=array("name"=>$user,"pwd"=>$pwd);
$add=$db->insert("biao",$arr);
//取所有数据
include("../db.class.php");
$db=new DB("db");
$arr=$db->getAll("select * from message");
//取单条数据
include("../db.class.php");
$db=new DB("db");
$arr=$db->getRow("select * from message");
//删除数据
include '../db.class.php';
$db = new DB('db');
$str ="id=$id";
$r = $db->delete('biao',$str);
$db->delete("ajax_update","id=$id");
//修改
$id=$_GET['id'];
$arr['title']=$title;
$db->update('ajax_update',$arr,"id=$id");
