如何更快地排序列表视图

本文关键字：列表 视图 排序 何更快 | 更新日期: 2023-09-27 18:18:59

我在MSDN中找到了ListView排序的解决方案…但是我发现代码要花太多的时间来显示ListView正确时，一列被点击…所以我要求一个加快速度的解决方案。我必须对包含超过10,000项的ListView进行排序。这是我的全部代码…

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Collections;
using System.Runtime.InteropServices;
namespace ListViewSorter
{
    class ListViewSorter
    {
        const Int32 HDF_SORTDOWN = 0x200;
        const Int32 HDF_SORTUP = 0x400;
        const Int32 HDI_FORMAT = 0x4;
        const Int32 HDM_GETITEM = 0x120b;
        const Int32 HDM_SETITEM = 0x120c;
        const Int32 LVM_GETHEADER = 0x101f;
        [DllImport("user32.dll", CharSet = CharSet.Auto)]
        static extern IntPtr SendMessage(IntPtr hWnd, UInt32 msg, IntPtr wParam, IntPtr lParam);
        [DllImport("user32.dll", CharSet = CharSet.Auto, EntryPoint = "SendMessage")]
        static extern IntPtr SendMessageLVCOLUMN(IntPtr hWnd, UInt32 msg, IntPtr wParam, ref LVCOLUMN lParam);
        [StructLayout(LayoutKind.Sequential)]
        public struct LVCOLUMN
        {
            public Int32 mask;
            public Int32 cx;
            [MarshalAs(UnmanagedType.LPTStr)]
            public string pszText;
            public IntPtr hbm;
            public Int32 cchTextMax;
            public Int32 fmt;
            public Int32 iSubItem;
            public Int32 iImage;
            public Int32 iOrder;
        }
        public void SetSortIcon( ListView listview, int ColumnIndex)
        {
            IntPtr clmHdr = SendMessage(listview.Handle, LVM_GETHEADER, IntPtr.Zero, IntPtr.Zero);
            SortOrder sorting = listview.Sorting;
            for (int i = 0; i < listview.Columns.Count; i++)
            {
                IntPtr clmPtr = new IntPtr(i);
                LVCOLUMN lvColumn = new LVCOLUMN();
                lvColumn.mask = HDI_FORMAT;
                SendMessageLVCOLUMN(clmHdr, HDM_GETITEM, clmPtr, ref lvColumn);
                if (sorting != SortOrder.None && i == ColumnIndex)
                {
                    if (sorting == SortOrder.Ascending)
                    {
                        lvColumn.fmt &= ~HDF_SORTDOWN;
                        lvColumn.fmt |= HDF_SORTUP;
                    }
                    else
                    {
                        lvColumn.fmt &= ~HDF_SORTUP;
                        lvColumn.fmt |= HDF_SORTDOWN;
                    }
                }
                else
                {
                    lvColumn.fmt &= ~HDF_SORTDOWN & ~HDF_SORTUP;
                }
                SendMessageLVCOLUMN(clmHdr, HDM_SETITEM, clmPtr, ref lvColumn);
            }
        }
        public int SortColumn(ListView listview, int ColumnIndex, int sortColumn)
        {
            if (ColumnIndex != sortColumn)
            {
                sortColumn = ColumnIndex;
                listview.Sorting = SortOrder.Ascending;
            }
            else
            {
                if (listview.Sorting == SortOrder.Ascending)
                    listview.Sorting = SortOrder.Descending;
                else
                    listview.Sorting = SortOrder.Ascending;
            }
            SetSortIcon(listview, sortColumn);
            listview.Sort();
            listview.ListViewItemSorter = new ListViewItemComparer(ColumnIndex,
                                                              listview.Sorting);
            return sortColumn;
        }
    }
    class ListViewItemComparer : IComparer
    {
        private int col;
        private SortOrder order;
        public ListViewItemComparer()
        {
            col = 0;
            order = SortOrder.Ascending;
        }
        public ListViewItemComparer(int column, SortOrder order)
        {
            col = column;
            this.order = order;
        }
        public int Compare(object x, object y)
        {
            int returnVal;
            try
            {
                System.DateTime firstDate =
                        DateTime.Parse(((ListViewItem)x).SubItems[col].Text);
                System.DateTime secondDate =
                        DateTime.Parse(((ListViewItem)y).SubItems[col].Text);
                returnVal = DateTime.Compare(firstDate, secondDate);
            }
            catch
            {
                returnVal = String.Compare(((ListViewItem)x).SubItems[col].Text,
                            ((ListViewItem)y).SubItems[col].Text);
            }
            if (order == SortOrder.Descending)
                returnVal *= -1;
            return returnVal;
        }
    }
}
有谁能帮我解决这个问题吗?

如何更快地排序列表视图

我现在想到的一种方法是使用od data-binding并设置VirtualMode http://msdn.microsoft.com/en-us/library/system.windows.forms.listview.virtualmode.aspx。属性为true。

这样做，您将实现以下目标:

  • 您的大自定义数据data-layer自定义管理。换句话说，您对数据进行排序并将其绑定到listview而不排序listview项。

  • listView.VirtualMode=true;将强制listview控件仅为ui中可见的项创建listview项。换句话说，如果你在datacollection中有10,000个项目，但在UI上我只能看到其中的15个，由于窗口尺寸，渲染和lustviewitem UI工件创建时间将只花在15上，而不是像你的情况那样花在10,000上。

我认为你应该尝试定义数据类型，而不是使用对象。强制编译器找出dt需要额外的时间。

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