php mysql数据库操作分页类

            return $str;
        }
        function show_next_last(){
            if ($this->page>=$this->total_pages){
                $str =  "<strong>".$this->img_btn[2]."</strong> <strong>".$this->img_btn[3]."</strong>";
            }else{
                $str = "<a href='".$this->url.($this->page+1)."'>".$this->img_btn[2]."</a> ";
                $str.= "<a href='".$this->url.$this->total_pages."'>".$this->img_btn[3]."</a>";
            }
            return $str;
        }
        function show_num_text(){
            $str = " 转到第 <input id='go_num_text' type='text' value='".$this->page."' style='border:0;border-bottom:1px solid #CCC;text-align:center;width:20px;'/> 页 ";
            $str.= "<a href='#' onClick="window.location='".$this->url."'+document.getElementById('go_num_text').value;" style='font-family: Arial, Helvetica, sans-serif;font-weight:bold;font-size:14px;'>[Go]</a>";
            return $str;
        }
        function show_num_select(){
            if ($this->total_pages<50){
                $str = "<select onchange="if(this.options[this.selectedIndex].value!=''){location=this.options[this.selectedIndex].value;}">";
                for ($i=1; $i<=$this->total_pages; $i++){
                    $str.= "<option value='".$this->url.$i."' ".($this->page==$i ? " selected='selected'":"").">".$i."</option>";