ListView虚拟模式的使用

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Windows.Forms;using System.Data;namespace app_ListView{    public class ListViewEx : ListView    {        #region 虚拟模式相关操作        ///<summary>        /// 前台行集合        ///</summary>        public List<ListViewItem> CurrentCacheItemsSource;        public ListViewEx()        {            this.CurrentCacheItemsSource = new List<ListViewItem>();            this.VirtualMode = true;            this.RetrieveVirtualItem += new RetrieveVirtualItemEventHandler(listView_RetrieveVirtualItem);        }        ///<summary>        /// 重置listview集合        ///</summary>        ///<param name="l"></param>        public void ReSet(IList<ListViewItem> l)        {            this.CurrentCacheItemsSource.Clear();            this.CurrentCacheItemsSource = new List<ListViewItem>();            foreach (var item in l)            {                this.CurrentCacheItemsSource.Add(item);            }            this.VirtualListSize = this.CurrentCacheItemsSource.Count;        }        ///<summary>        /// 虚拟模式事件        ///</summary>        ///<param name="sender"></param>        ///<param name="e"></param>        private void listView_RetrieveVirtualItem(object sender, RetrieveVirtualItemEventArgs e)        {            if (this.CurrentCacheItemsSource == null || this.CurrentCacheItemsSource.Count == 0)            {                return;            }            ListViewItem lv = this.CurrentCacheItemsSource[e.ItemIndex];            e.Item = lv;        }        ///<summary>        /// 获取选中的第一行的指定tag值        ///</summary>        ///<param name="key"></param>        ///<returns></returns>        public string FirstSelectItemValue(string key)        {            int i = GetColumnsIndex(key);            return this.CurrentCacheItemsSource[this.SelectedIndices[0]].SubItems[i].Text;        }        ///<summary>        /// 获取列名的索引        ///</summary>        ///<param name="key"></param>        ///<returns></returns>        public int GetColumnsIndex(string key)        {            int i = 0;            for (; i < this.Columns.Count; i++)            {                if (this.Columns[i].Name == key)                {                    break;                }            }            return i;        }        ///<summary>        /// 获取选中项        ///</summary>        ///<returns></returns>        public List<ListViewItem> GetSelectItem()        {            List<ListViewItem> l = new List<ListViewItem>();            foreach (var item in this.SelectedIndices)            {                l.Add(this.CurrentCacheItemsSource[int.Parse(item.ToString())]);            }            return l;        }        ///<summary>        /// 获取选中行的某列集合        ///</summary>        ///<param name="key"></param>        ///<returns></returns>        public List<string> GetListViewField(string key)        {            List<string> ids = new List<string>();            foreach (var item in this.SelectedIndices)            {                string id = this.CurrentCacheItemsSource[int.Parse(item.ToString())].SubItems[GetColumnsIndex(key)].Text;                ids.Add(id);            }            return ids;        }        private ListViewItemComparer mySorter;        ///<summary>        /// 排序        ///</summary>        ///<param name="e"></param>        protected override void OnColumnClick(ColumnClickEventArgs e)        {            base.OnColumnClick(e);            string dbType = this.Columns[e.Column].Tag.ToString();            if (this.mySorter == null)            {                this.mySorter = new ListViewItemComparer(e.Column, SortOrder.Ascending, dbType);            }            else            {                if (this.mySorter.SortColumn == e.Column)                {                    if (this.mySorter.Order == SortOrder.Ascending)                    {                        this.mySorter.Order = SortOrder.Descending;                    }                    else                    {                        this.mySorter.Order = SortOrder.Ascending;                    }                }                else                {                    this.mySorter.SortColumn = e.Column;                    this.mySorter.Order = SortOrder.Ascending;                }                this.mySorter.DbType = dbType;                this.CurrentCacheItemsSource.Sort(this.mySorter);                this.Invalidate();            }        }        #endregion        #region 普通模式下排序        /*普通模式下排序        public void ReLoadColumn()        {            this.ListViewItemSorter = new ListViewItemComparer(0, SortOrder.Ascending, this.Columns[0].Tag.ToString());        }        protected override void OnColumnClick(ColumnClickEventArgs e)        {            base.OnColumnClick(e);            string dbType = this.Columns[e.Column].Tag.ToString();            if (this.ListViewItemSorter == null)            {                this.ListViewItemSorter = new ListViewItemComparer(e.Column, SortOrder.Ascending, dbType);            }            else            {                ListViewItemComparer comparer = this.ListViewItemSorter as ListViewItemComparer;                if (comparer.SortColumn == e.Column)                {                    if (comparer.Order == SortOrder.Ascending)                    {                        comparer.Order = SortOrder.Descending;                    }                    else                    {                        comparer.Order = SortOrder.Ascending;                    }                }                else                {                    comparer.SortColumn = e.Column;                    comparer.Order = SortOrder.Ascending;                }                //MessageBox.Show(dbType);                comparer.DbType = dbType;                //仅仅改变了ListViewItemSorter属性值，这里不会自动调用Sort()方法，需要显式指定执行Sort()方法实现排序。                this.Sort();            }        }        */        #endregion        #region ListView排序逻辑        ///<summary>        /// ListView排序逻辑        ///</summary>        private class ListViewItemComparer : System.Collections.Generic.IComparer<ListViewItem>        {            public string DbType;            public ListViewItemComparer()            {                this.SortColumn = 0;                this.Order = SortOrder.None;            }            public ListViewItemComparer(int column)                : this()            {                this.SortColumn = column;            }            ///<summary>            ///             ///</summary>            ///<param name="column">哪列</param>            ///<param name="sortOrder">排序方式</param>            ///<param name="dbType">类型</param>            public ListViewItemComparer(int column, SortOrder sortOrder, string dbType)                : this(column)            {                Order = sortOrder;                DbType = dbType.ToLower();            }            #region IComparer 成员            public int Compare(ListViewItem x, ListViewItem y)            {                int result = 0;                string c1 = "";                string c2 = "";                try                {                    c1 = x.SubItems[this.SortColumn].Text;                    c2 = y.SubItems[this.SortColumn].Text;                }                catch (Exception ex)                {                    //    MessageBox.Show(ex.Message);                    return 0;                }                switch (DbType)                {                    case "int":                        result = Fn.IsInt(c1, 0) - Fn.IsInt(c2, 0);                        break;                    case "datetime":                        DateTime t1 = Fn.IsDate(c1, DateTime.MinValue);                        DateTime t2 = Fn.IsDate(c2, DateTime.MinValue);                        if (DateTime.TryParse(c1, out t1) && DateTime.TryParse(c2, out t2))                        {                            int cha1 = Fn.IsInt((t1 - t2).TotalSeconds.ToString(), 0);                            result = Fn.IsInt((t1 - t2).TotalSeconds.ToString(), 0);                            if (cha1 == 0)                                result = 0;                            else if (cha1 < 0)                                result = -1;                            else                                result = 1;                        }                        else                        {                            result = string.Compare(c1, c2);                        }                        break;                    case "double":                        double d1 = Fn.IsDouble(c1, 0);                        double d2 = Fn.IsDouble(c2, 0);                        if (d1 == d2)                            result = 0;                        else if (d1 < d2)                            result = -1;                        else                            result = 1;                        break;                    default:                        result = string.Compare(c1, c2);                        break;                }                if (this.Order == SortOrder.Ascending)                {                    return result;                }                else if (this.Order == SortOrder.Descending)                {                    return (-result);                }                else                {                    return 0;                }            }            #endregion            ///<summary>            /// 当前排序列            ///</summary>            public int SortColumn            {                get;                set;            }            ///<summary>            /// 当前列排序方式            ///</summary>            public SortOrder Order            {                get;                set;            }        }        #endregion        public void Fill_Lv(DataSet ds)        {            this.View = View.Details;            this.FullRowSelect = true;            this.GridLines = true;              DataTable table = ds.Tables[0];            if (ds != null && ds.Tables.Count > 0)            {                foreach (DataColumn col in table.Columns)                {                    ColumnHeader ch = new ColumnHeader();                    ch.TextAlign = System.Windows.Forms.HorizontalAlignment.Left;                    ch.Text = col.Caption;                    ch.Width = 100;                    this.Columns.Add(ch);                }                List<ListViewItem> lstItem = new List<ListViewItem>();                foreach (DataRow dr in table.Rows)                {                    string[] str = new string[table.Columns.Count];                    for (int i = 0; i < table.Columns.Count; i++)                    {                        str[i] = dr[i].ToString();                    }                    ListViewItem lst1 = new ListViewItem(str, 0);                    //lst1.ImageIndex = Convert.ToInt32(dr["Ste"]);                      lstItem.Add(lst1);                }                AddLVRow(lstItem);            }            this.AutoResizeColumns(ColumnHeaderAutoResizeStyle.HeaderSize);            this.Columns[this.Columns.Count - 1].Width -= 50;        }        protected void AddLVCol(string pName, string pTag, string pText, int pWidth)        {            ColumnHeader ch = new ColumnHeader();            ch.Name = pName;            ch.Tag = pTag;            ch.Text = pText;            ch.Width = pWidth;            this.Columns.Add(ch);        }        protected void AddLVRow(List<ListViewItem> lvItem)        {            this.ReSet(lvItem);        }    }    public static class Fn    {        public static int IsInt(object obj1, int i1)        {            try            {                return Convert.ToInt32(obj1);            }            catch (System.Exception ex)            {                return i1;            }        }        public static double IsDouble(object obj1, double d1)        {            try            {                return Convert.ToDouble(obj1);            }            catch (System.Exception ex)            {                return d1;            }        }        public static DateTime IsDate(object obj1, DateTime datTim1)        {            try            {                return Convert.ToDateTime(obj1);            }            catch (System.Exception ex)            {                return datTim1;            }        }    }}

使用方法：

    public partial class Form1 : Form    {        ListViewEx lv1 = new ListViewEx();        CADO ado1 = new CADO();        public Form1()        {            InitializeComponent();        }        private void Form1_Load(object sender, EventArgs e)        {            lv1.Parent = this;            lv1.Dock = DockStyle.Fill;            lv1.Show();            DataSet ds1 = ado1.sel1("select top 1000 * from tabTimeData");            lv1.Fill_Lv(ds1);        }    }