Question

想知道你在哪里发现并纠正我做错了什么。我需要实现一些分页，我遇到的问题是索引与页面不同步

EG按下链接“2”第2页我得到与第3页（21-30）等相关的数据......

CHAR

我把一个简单的样本放在一起

模型

Current Result
1  (1-10)   correct
2  (21-30)  wrong
3  (31-40)  wrong
4  (41-50)  wrong
    etc...

Wanted Result

1 (1-10) 
2  (2-20)
3) (21-30)
4  (31-40)
    etc...

视图模型

public class Product
{
    public string Name { get; set; }
    public string Category { get; set; }
}

控制器

public class ProductViewModel
{
    public IEnumerable<Product> Items { get; set; }
    public Pager Pager { get; set; }
}

寻呼机

public class ProductController : Controller
{
    public ActionResult Index(int? page)
    {
        var allProducts = GetProducts();

        int pageIndex;
        if (page <= 1)
        {
            pageIndex = 0;
        }
        else
        {
            pageIndex = page ?? 0;
        }

        int itemsXPage = 10;

        var paginatedProducts = allProducts.Skip(pageIndex * itemsXPage).Take(itemsXPage);

        var pager = Pager
           .Items(allProducts.Count())
           .PerPage(10)
           .Move(page ?? 0)
           .Segment(5)
           .Center();

        var viewModel = new ProductViewModel
        {
            Items = paginatedProducts,
            Pager = pager
        };
        return View(viewModel);
    }

    public IEnumerable<Product> GetProducts()
    {
        List<Product> products = new List<Product>();
        for (int i = 1; i < 150; i++)
        {
            var product = new Product { Name = "Product" + i, Category = "Shoes" };
            products.Add(product);
        }
        return products;
    }

查看

     link http://www.superstarcoders.com/blogs/posts/pager-for-asp-net-mvc.aspx

     public  class Pager : IEnumerable<int>
    {
        private int _numberOfPages;
        private int _skipPages;
        private int _takePages;
        private int _currentPageIndex;
        private int _itemsPerPage;

        private Pager()
        {
        }

        private Pager(Pager pager)
        {
            NumberOfItems = pager.NumberOfItems;
            _currentPageIndex = pager._currentPageIndex;
            _numberOfPages = pager._numberOfPages;
            _takePages = pager._takePages;
            _skipPages = pager._skipPages;
            _itemsPerPage = pager._itemsPerPage;
        }

        /// <summary>
        /// Creates a pager for the given number of items.
        /// </summary>
        public static Pager Items(int numberOfItems)
        {
            return new Pager
            {
                NumberOfItems = numberOfItems,
                _currentPageIndex = 0,
                _numberOfPages = 1,
                _skipPages = 0,
                _takePages = 1,
                _itemsPerPage = numberOfItems
            };
        }

        /// <summary>
        /// Specifies the number of items per page.
        /// </summary>
        public Pager PerPage(int itemsPerPage)
        {
            int numberOfPages = (NumberOfItems + itemsPerPage - 1) / itemsPerPage;

            return new Pager(this)
            {
                _numberOfPages = numberOfPages,
                _skipPages = 0,
                _takePages = numberOfPages - _currentPageIndex + 1,
                _itemsPerPage = itemsPerPage
            };
        }

        /// <summary>
        /// Moves the pager to the given page index
        /// </summary>
        public Pager Move(int pageIndex)
        {
            return new Pager(this)
            {
                _currentPageIndex = pageIndex
            };
        }

        /// <summary>
        /// Segments the pager so that it will display a maximum number of pages.
        /// </summary>
        public Pager Segment(int maximum)
        {
            int count = Math.Min(_numberOfPages, maximum);

            return new Pager(this)
            {
                _takePages = count,
                _skipPages = Math.Min(_skipPages, _numberOfPages - count),
            };
        }

        /// <summary>
        /// Centers the segment around the current page
        /// </summary>
        /// <returns></returns>
        public Pager Center()
        {
            int radius = ((_takePages + 1) / 2);

            return new Pager(this)
            {
                _skipPages = Math.Min(Math.Max(_currentPageIndex - radius, 0), _numberOfPages - _takePages)
            };
        }

        public IEnumerator<int> GetEnumerator()
        {
            return Enumerable.Range(_skipPages + 1, _takePages).GetEnumerator();
        }

        IEnumerator IEnumerable.GetEnumerator()
        {
            return GetEnumerator();
        }

        public bool IsPaged { get { return NumberOfItems > _itemsPerPage; } }

        public int NumberOfPages { get { return _numberOfPages; } }

        public bool IsUnpaged { get { return _numberOfPages == 1; } }

        public int CurrentPageIndex { get { return _currentPageIndex; } }

        public int NextPageIndex { get { return _currentPageIndex + 1; } }

        public int LastPageIndex { get { return _numberOfPages; } }

        public int FirstPageIndex { get { return 1; } }

        public bool HasNextPage { get { return _currentPageIndex < _numberOfPages && _numberOfPages > 1; } }

        public bool HasPreviousPage { get { return _currentPageIndex > 1 && _numberOfPages > 1; } }

        public int PreviousPageIndex { get { return _currentPageIndex - 1; } }

        public bool IsSegmented { get { return _skipPages > 0 || _skipPages + 1 + _takePages < _numberOfPages; } }

        public bool IsEmpty { get { return _numberOfPages < 1; } }

        public bool IsFirstSegment { get { return _skipPages == 0; } }

        public bool IsLastSegment { get { return _skipPages + 1 + _takePages >= _numberOfPages; } }

        public int ItemStart { get { return CurrentPageIndex * _itemsPerPage + 1; } }

        public int ItemEnd
        {
            get { return Math.Min(CurrentPageIndex * _itemsPerPage + _itemsPerPage, NumberOfItems); }
        }

        public int NumberOfItems { get; set; }
    }

你能发现我做错了吗？

Answer 1

这是错误的

if (page <= 1)
    {
        pageIndex = 0;
    }
    else
    {
        pageIndex = page ?? 0;
    }

只是递减你的页码而不是这个，看起来你的页面var是基于1但索引是基于0。

因为你有1个进入第一页获得页面索引0，但如果你传入2它保持2，所以没有办法得到实际的pageindex为1

分页问题mvc .Index与pagenumber不同步

1 个答案: