原文:

在WPF中，通常会选用DataGrid/ListView进行数据展示，如果数据量不多，可以直接一个页面显示出来。如果数据量很大，2000条数据，一次性显示在一个页面中，不仅消耗资源，而且用户体验也很糟糕。这篇博客将介绍如何创建一个分页控件。

为了简单起见，这个分页控件目前只有 首页/上一页/下一页/末页/总页数/第几页 等功能。实现思路，首页/上一页/下一页/末页 这四个通过路由事件来实现，在使用时可以使用命令进行绑定，或者直接使用均可。总页数和第几页通过依赖属性来实现，使用时将页数进行绑定显示即可。示例代码如下：

Pager控件：

C#:

public partial class Pager : UserControl    {        public static RoutedEvent FirstPageEvent;        public static RoutedEvent PreviousPageEvent;        public static RoutedEvent NextPageEvent;        public static RoutedEvent LastPageEvent;        public static readonly DependencyProperty CurrentPageProperty;        public static readonly DependencyProperty TotalPageProperty;        public string CurrentPage        {            get { return (string)GetValue(CurrentPageProperty); }            set { SetValue(CurrentPageProperty, value); }        }        public string TotalPage        {            get { return (string)GetValue(TotalPageProperty); }            set { SetValue(TotalPageProperty, value); }        }        public Pager()        {            InitializeComponent();        }        static Pager()        {            FirstPageEvent = EventManager.RegisterRoutedEvent("FirstPage", RoutingStrategy.Direct, typeof(RoutedEventHandler), typeof(Pager));            PreviousPageEvent = EventManager.RegisterRoutedEvent("PreviousPage", RoutingStrategy.Direct, typeof(RoutedEventHandler), typeof(Pager));            NextPageEvent = EventManager.RegisterRoutedEvent("NextPage", RoutingStrategy.Direct, typeof(RoutedEventHandler), typeof(Pager));            LastPageEvent = EventManager.RegisterRoutedEvent("LastPage", RoutingStrategy.Direct, typeof(RoutedEventHandler), typeof(Pager));            CurrentPageProperty = DependencyProperty.Register("CurrentPage", typeof(string), typeof(Pager), new PropertyMetadata(string.Empty,new PropertyChangedCallback(OnCurrentPageChanged)));            TotalPageProperty = DependencyProperty.Register("TotalPage", typeof(string), typeof(Pager), new PropertyMetadata(string.Empty,new PropertyChangedCallback(OnTotalPageChanged)));        }        public event RoutedEventHandler FirstPage        {            add { AddHandler(FirstPageEvent, value); }            remove { RemoveHandler(FirstPageEvent, value); }        }        public event RoutedEventHandler PreviousPage        {            add { AddHandler(PreviousPageEvent, value); }            remove { RemoveHandler(PreviousPageEvent, value); }        }        public event RoutedEventHandler NextPage        {            add { AddHandler(NextPageEvent, value); }            remove { RemoveHandler(NextPageEvent, value); }        }        public event RoutedEventHandler LastPage        {            add { AddHandler(LastPageEvent, value); }            remove { RemoveHandler(LastPageEvent, value); }        }        public static void OnTotalPageChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)        {            Pager p = d as Pager;            if(p != null)            {                Run rTotal = (Run)p.FindName("rTotal");                rTotal.Text = (string)e.NewValue;            }        }        private static void OnCurrentPageChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)        {            Pager p = d as Pager;            if(p != null)            {                Run rCurrrent = (Run)p.FindName("rCurrent");                rCurrrent.Text = (string)e.NewValue;            }        }        private void FirstPageButton_Click(object sender, RoutedEventArgs e)        {            RaiseEvent(new RoutedEventArgs(FirstPageEvent, this));        }        private void PreviousPageButton_Click(object sender, RoutedEventArgs e)        {            RaiseEvent(new RoutedEventArgs(PreviousPageEvent, this));        }        private void NextPageButton_Click(object sender, RoutedEventArgs e)        {            RaiseEvent(new RoutedEventArgs(NextPageEvent, this));        }        private void LastPageButton_Click(object sender, RoutedEventArgs e)        {            RaiseEvent(new RoutedEventArgs(LastPageEvent, this));        }    }

在MainWindow中,

XAML:

MainViewModel类：

public class MainViewModel : ViewModel    {        private ICommand _firstPageCommand;        public ICommand FirstPageCommand        {            get            {                return _firstPageCommand;            }            set            {                _firstPageCommand = value;            }        }        private ICommand _previousPageCommand;        public ICommand PreviousPageCommand        {            get            {                return _previousPageCommand;            }            set            {                _previousPageCommand = value;            }        }        private ICommand _nextPageCommand;        public ICommand NextPageCommand        {            get            {                return _nextPageCommand;            }            set            {                _nextPageCommand = value;            }        }        private ICommand _lastPageCommand;        public ICommand LastPageCommand        {            get            {                return _lastPageCommand;            }            set            {                _lastPageCommand = value;            }        }        private int _pageSize;        public int PageSize        {            get            {                return _pageSize;            }            set            {                if(_pageSize != value)                {                    _pageSize = value;                    OnPropertyChanged("PageSize");                }            }        }        private int _currentPage;        public int CurrentPage        {            get            {                return _currentPage;            }            set            {                if(_currentPage != value)                {                    _currentPage = value;                    OnPropertyChanged("CurrentPage");                }            }        }        private int _totalPage;        public int TotalPage        {            get            {                return _totalPage;            }            set            {                if(_totalPage != value)                {                    _totalPage = value;                    OnPropertyChanged("TotalPage");                }            }        }        private ObservableCollection
         
           _fakeSoruce;        public ObservableCollection
          
            FakeSource        {            get            {                return _fakeSoruce;            }            set            {                if(_fakeSoruce != value)                {                    _fakeSoruce = value;                    OnPropertyChanged("FakeSource");                }            }        }        private List
           
             _source;        public MainViewModel()        {            _currentPage = 1;            _pageSize = 20;            FakeDatabase fake = new FakeDatabase();            _source = fake.GenerateFakeSource();            _totalPage = _source.Count / _pageSize;            _fakeSoruce = new ObservableCollection
            
             ();            List
             
               result = _source.Take(20).ToList();            _fakeSoruce.Clear();            _fakeSoruce.AddRange(result);            _firstPageCommand = new DelegateCommand(FirstPageAction);            _previousPageCommand = new DelegateCommand(PreviousPageAction);            _nextPageCommand = new DelegateCommand(NextPageAction);            _lastPageCommand = new DelegateCommand(LastPageAction);        }        private void FirstPageAction()        {            CurrentPage = 1;            var result = _source.Take(_pageSize).ToList();            _fakeSoruce.Clear();            _fakeSoruce.AddRange(result);        }        private void PreviousPageAction()        {            if(CurrentPage == 1)            {                return;            }            List
              
                result = new List
               
                (); if(CurrentPage == 2) { result = _source.Take(_pageSize).ToList(); } else { result = _source.Skip((CurrentPage - 2) * _pageSize).Take(_pageSize).ToList(); } _fakeSoruce.Clear(); _fakeSoruce.AddRange(result); CurrentPage--; } private void NextPageAction() { if(CurrentPage == _totalPage) { return; } List
                
                  result = new List
                 
                  (); result = _source.Skip(CurrentPage * _pageSize).Take(_pageSize).ToList(); _fakeSoruce.Clear(); _fakeSoruce.AddRange(result); CurrentPage++; } private void LastPageAction() { CurrentPage = TotalPage; int skipCount = (_totalPage - 1) * _pageSize; int takeCount = _source.Count - skipCount; var result = _source.Skip(skipCount).Take(takeCount).ToList(); _fakeSoruce.Clear(); _fakeSoruce.AddRange(result); } }
                 
                
               
              
             
            
           
          
         

绑定到UI的数据源只是需要显示的数据，不会把所有数据都取出来。当选择显示页数时，只需要将新的数据源附上即可。

总结：如果需要对该分页控件进行扩展，例如，增加每页显示条数功能，只需要在Pager控件中增加相应的依赖属性即可。

感谢您的阅读，代码点击下载。