PHP realizes pagination function (1) Previous/Next (pagination with classification function)

The following method is developed based on the THINKPHP5 framework to realize the previous/next page button-type paging function, as shown in the figure below. The

first is a simple paging that does not involve the classification function.

Controller code

/*
 *分页功能
 * 参数：p 当前页码数
 *      listpage 每页显示的数据条数
 *      totalpage 总页数
 * */
public function index(){
    
    
	$p=input('p',1,'intval');//当前页码数，默认显示第一页
	$listpage=input('listpage',8,'intval');//每页显示的数据条数
	$count=Db::name('shujubiao')->count();//数据总数
	$totalpage=ceil($count/$listpage);//总页数
	$product=Db::name('shujubiao')->page($p,$listpage)->select();
	
	$this->assign('product',$product);
	$this->assign('p',$p);
	$this->assign('totalpage',$totalpage);
	return $this->view->fetch('页面');
}

Front-end code, style self-debug

<div class="page-box mt50 box flex_b">
	<input type="hidden" id="page" value="{$p}">
    <input type="hidden" id="totalpage" value="{$totalpage}">
    <a href="javascript:;" class="page-item up">上一页</a>
    <a href="javascript:;" class="page-item down">下一页</a>
</div>

js code

//分页
//上一页
$(document).on('click', '.page-box .up', function() {
    
    
    var page = $("#page").val();
    page--;
    if (page < 1) {
    
    
        page = 1;
        alert('已经是第一页了');
        return false;
    }
    location.href = "/模块名/控制器名/方法名/p/" + page + '.html';//跳转到自己的控制器方法
});
//下一页
$(document).on('click', '.page-box .down', function() {
    
    
    var page = $("#page").val();
    var totalpage = $("#totalpage").val();
    page++;
    if (page > totalpage) {
    
    
        page = totalpage;
        alert('已经是最后一页了');
        return false;
    }
     location.href = "/模块名/控制器名/方法名/p/" + page + '.html';//跳转到自己的控制器方法
});

The above can realize simple previous/next page functions;
*
*

The paging function is usually mixed with the classification function. The following is the paging code with the classification function in this style.

Controller code (compared with the normal paging function above, only the classification where condition is added)

public function index(){
    
    
	//参数 class_id 分类id
	$class_id=input('class_id','','intval');//参数@所属分类id
	if(!$class_id){
    
    
	    //如果没有分类，显示全部商品
	}else{
    
    
	    $classidarr=[];
	    $classidarr[0]=$class_id;
	    $classidarr=array_merge($classidarr,$this->loop($class_id));//所有下级分类id集合
	    $where['pclass_id']=array('in',$classidarr);//pclass_id为关联外键
	}
	
	//下面代码和普通分页代码基本一样，添加一个分类的where条件
	$p=input('p',1,'intval');//当前页码数，默认显示第一页
	$listpage=input('listpage',8,'intval');//每页显示的数据条数
	$count=Db::name('shujubiao')->where($where)->count();//对应分类下的数据总数
	$totalpage=ceil($count/$listpage);//总页数
	$product=Db::name('shujubiao')->where($where)->page($p,$listpage)->select();
	
	$this->assign('product',$product);
	$this->assign('p',$p);
	$this->assign('totalpage',$totalpage);
	$this->assign('class_id',$class_id);//分类id
	return $this->view->fetch('页面');
}
/*
* 获得所有下级分类id
* 参数：$pid 上级分类id
* */
private function loop($pid){
    
    
   $idsarr=db('分类表')->where('pid',$pid)->column('id');
   if($idsarr){
    
    
       foreach($idsarr as $id){
    
    
           $idsarr=array_merge($idsarr,$this->loop($id));
       }
   }
   return $idsarr;
}

Front-end code, style self-debugging (compared with the above html code, the transfer of classified parameters is added)

<div class="page-box mt50 box flex_b">
	<input type="hidden" id="page" value="{$p}">
    <input type="hidden" id="totalpage" value="{$totalpage}">
    <input type="hidden" id="class_id" value="{$class_id}">
    <a href="javascript:;" class="page-item up">上一页</a>
    <a href="javascript:;" class="page-item down">下一页</a>
</div>

js code (compared with the above js code, classification judgment and parameter transfer are added)

//分页
//上一页
$(document).on('click', '.page-box .up', function() {
    
    
    var page = $("#page").val();
    var classid = $("#class_id").val();
    if (!classid) {
    
    
        classid = 0;
    }
    page--;
    if (page < 1) {
    
    
        page = 1;
        alert('已经是第一页了');
        return false;
    }
    location.href = "/模块名/控制器名/方法名/p/" + page+ "/class_id/" + classid+ '.html';//跳转到自己的控制器方法
});
//下一页
$(document).on('click', '.page-box .down', function() {
    
    
    var page = $("#page").val();
    var totalpage = $("#totalpage").val();
    var classid = $("#class_id").val();
    if (!classid) {
    
    
        classid = 0;
    }
    page++;
    if (page > totalpage) {
    
    
        page = totalpage;
        alert('已经是最后一页了');
        return false;
    }
     location.href = "/模块名/控制器名/方法名/p/" + page+ "/class_id/" + classid + '.html';//跳转到自己的控制器方法
});

The above can realize the previous page/next page function combined with classification.
The method of parameter transmission is not limited, and you can modify and debug according to your own requirements.