根据老外的方法,GridVew实现多列排序.

代碼如下：

  1Using directives#region Using directives
  2
  3using System;
  4using System.Collections.Generic;
  5using System.ComponentModel;
  6using System.Text;
  7using System.Web.UI;
  8using System.Web.UI.WebControls;
  9
 10#endregion
 11
 12namespace GridControl
 13{
 14 
 15    public class ctGridView: GridView
 16    {
 17        Properties#region Properties
 18        /**//// <summary>
 19        /// Enable/Disable MultiColumn Sorting.
 20        /// </summary>
 21        [
 22        Description("Whether Sorting On more than one column is enabled"),
 23        Category("Behavior"),
 24        DefaultValue("false"),
 25        ]
 26        public bool AllowMultiColumnSorting
 27        {
 28            get
 29            {
 30                object o = ViewState["EnableMultiColumnSorting"];
 31                return (o != null ? (bool)o : false);
 32            }
 33            set
 34            {
 35                AllowSorting = true;
 36                ViewState["EnableMultiColumnSorting"] = value;
 37            }
 38        }
 39        /**//// <summary>
 40        /// Get or Set Image location to be used to display Ascending Sort order.
 41        /// </summary>
 42        [
 43        Description("Image to display for Ascending Sort"),
 44        Category("Misc"),
 45        Editor("System.Web.UI.Design.UrlEditor",typeof(System.Drawing.Design.UITypeEditor)),
 46        DefaultValue(""),
 47        
 48        ]
 49        public string SortAscImageUrl
 50        {
 51            get
 52            {
 53                object o = ViewState["SortImageAsc"];
 54                return (o != null ? o.ToString() : "");
 55            }
 56            set
 57            {
 58                ViewState["SortImageAsc"] = value;
 59            }
 60        }
 61        /**//// <summary>
 62        /// Get or Set Image location to be used to display Ascending Sort order.
 63        /// </summary>
 64        [
 65        Description("Image to display for Descending Sort"),
 66        Category("Misc"),
 67        Editor("System.Web.UI.Design.UrlEditor",typeof(System.Drawing.Design.UITypeEditor)),
 68        DefaultValue(""),
 69        ]
 70        public string SortDescImageUrl
 71        {
 72            get
 73            {
 74                object o = ViewState["SortImageDesc"];
 75                return (o != null ? o.ToString() : "");
 76            }
 77            set
 78            {
 79                ViewState["SortImageDesc"] = value;
 80            }
 81        }
 82        #endregion
 83        Life Cycle#region Life Cycle
 84
 85
 86        protected override void OnSorting(GridViewSortEventArgs e)
 87        {
 88            if (AllowMultiColumnSorting)
 89                e.SortExpression  = GetSortExpression(e);
 90            
 91            base.OnSorting(e);
 92        }
 93
 94        protected override void OnRowCreated(GridViewRowEventArgs e)
 95        {
 96            if (e.Row.RowType == DataControlRowType.Header)
 97            {
 98                if (SortExpression != String.Empty)
 99                    DisplaySortOrderImages(SortExpression, e.Row);
100            }
101            base.OnRowCreated(e);
102        }
103 
104        #endregion
105        Protected Methods#region Protected Methods
106        /**//// <summary>
107        ///  Get Sort Expression by Looking up the existing Grid View Sort Expression 
108        /// </summary>
109        protected string GetSortExpression(GridViewSortEventArgs e)
110        {
111            string[] sortColumns = null;
112            string sortAttribute = SortExpression;
113
114            //Check to See if we have an existing Sort Order already in the Grid View.    
115            //If so get the Sort Columns into an array
116            if (sortAttribute != String.Empty)
117            {
118                sortColumns = sortAttribute.Split(",".ToCharArray());
119            }
120
121            //if User clicked on the columns in the existing sort sequence.
122            //Toggle the sort order or remove the column from sort appropriately
123
124            if (sortAttribute.IndexOf(e.SortExpression) > 0 || sortAttribute.StartsWith(e.SortExpression))
125                sortAttribute = ModifySortExpression(sortColumns, e.SortExpression);
126            else
127                sortAttribute += String.Concat(",", e.SortExpression, " ASC ");
128            return sortAttribute.TrimStart(",".ToCharArray()).TrimEnd(",".ToCharArray()) ;
129
130        }
131        /**//// <summary>
132        ///  Toggle the sort order or remove the column from sort appropriately
133        /// </summary>
134        protected string ModifySortExpression(string[] sortColumns, string sortExpression)
135        {
136
137            string ascSortExpression = String.Concat(sortExpression, " ASC ");
138            string descSortExpression = String.Concat(sortExpression, " DESC ");
139
140            for (int i = 0; i < sortColumns.Length; i++)
141            {
142
143                if (ascSortExpression.Equals(sortColumns[i]))
144                {
145                    sortColumns[i] = descSortExpression;
146                }
147
148                else if (descSortExpression.Equals(sortColumns[i]))
149                {
150                    Array.Clear(sortColumns, i, 1);
151                }
152            }
153
154            return String.Join(",", sortColumns).Replace(",,", ",").TrimStart(",".ToCharArray());
155
156        }
157        /**//// <summary>
158        ///  Lookup the Current Sort Expression to determine the Order of a specific item.
159        /// </summary>
160        protected void SearchSortExpression(string[] sortColumns, string sortColumn, out string sortOrder, out int sortOrderNo)
161        {
162            sortOrder = "";
163            sortOrderNo = -1;
164            for (int i = 0; i < sortColumns.Length; i++)
165            {
166                if (sortColumns[i].StartsWith(sortColumn))
167                {
168                    sortOrderNo = i + 1;
169                    if (AllowMultiColumnSorting)
170                        sortOrder = sortColumns[i].Substring(sortColumn.Length).Trim();
171                    else
172                        sortOrder = ((SortDirection == SortDirection.Ascending) ? "ASC" : "DESC");
173                }
174            }
175        }
176        /**//// <summary>
177        ///  Display a graphic image for the Sort Order along with the sort sequence no.
178        /// </summary>
179        protected void DisplaySortOrderImages(string sortExpression,  GridViewRow dgItem)
180        {
181            string[] sortColumns = sortExpression.Split(",".ToCharArray());
182
183            for (int i = 0; i < dgItem.Cells.Count; i++)
184            {
185                if (dgItem.Cells[i].Controls.Count > 0 && dgItem.Cells[i].Controls[0] is LinkButton)
186                {
187                    string sortOrder;
188                    int sortOrderNo;
189                    string column = ((LinkButton)dgItem.Cells[i].Controls[0]).CommandArgument;
190                    SearchSortExpression(sortColumns, column, out sortOrder, out sortOrderNo);
191                    if (sortOrderNo > 0)
192                    {
193                        string sortImgLoc = (sortOrder.Equals("ASC") ? SortAscImageUrl : SortDescImageUrl);
194
195                        if (sortImgLoc != String.Empty)
196                        {
197                            Image imgSortDirection = new Image();
198                            imgSortDirection.ImageUrl = sortImgLoc;
199                            dgItem.Cells[i].Controls.Add(imgSortDirection);
200                            Label lblSortOrder = new Label();
201                            lblSortOrder.Font.Size = FontUnit.Small;
202                            lblSortOrder.Text = sortOrderNo.ToString();
203                            dgItem.Cells[i].Controls.Add(lblSortOrder);
204
205                        }
206                        else
207                        {
208
209                            Label lblSortDirection = new Label();
210                            lblSortDirection.Font.Size = FontUnit.XSmall;
211                            lblSortDirection.Font.Name = "webdings";
212                            lblSortDirection.EnableTheming = false;
213                            lblSortDirection.Text = (sortOrder.Equals("ASC") ? "5" : "6");
214                            dgItem.Cells[i].Controls.Add(lblSortDirection);
215
216                            if (AllowMultiColumnSorting)
217                            {
218                                Literal litSortSeq = new Literal();
219                                litSortSeq.Text = sortOrderNo.ToString();
220                                dgItem.Cells[i].Controls.Add(litSortSeq);
221                                
222                            }
223
224
225                        }
226
227
228                   
229
230                    }
231
232                }
233            }
234
235        }
236        #endregion
237    }
238}

但是感覺很不爽
以下是一些相关的資料
http://aspnet.4guysfromrolla.com/demos/dgExample37.aspx
http://msdn.microsoft.com/library/en-us/cpguide/html/cpconsortingfilteringdatausingdataview.asp
http://dotnetjunkies.com/WebLog/thomasswilliams/archive/2005/11/09/133667.aspx
http://aspalliance.com/666