分割，截取连接字符串

if (!empty($iddstr)) {
    if (!empty($iddstr)) {
        $darr=explode("\r\n",$iddstr);
        foreach ($darr as $key => $value) {
            $lp_num = explode("——",$value);
            if(strlen($lp_num[0])!=10||strlen($lp_num[1])!=10){
                $tt = $key + 1;
                $this->assign('iddstr',$iddstr);
                $this->error("第".$tt."个联票号段的位数不为10");
            }
            if($key == 0){
                $where .= " and (left(lianpiaono,10) between '" . $lp_num[0] . "' and '" . $lp_num[1] . "')";
            }else{
                $where .= " or (left(lianpiaono,10) between '" . $lp_num[0] . "' and '" . $lp_num[1] . "')";
            }
        }
     }      
}