如何在GridView中进行排序

我有以下GirdView显示一些具有修改日期的文件：

      <asp:LinkButton ID="lnkDownload" Text="Download" runat="server" CommandArgument='' OnClick="DownloadFile" />     <asp:LinkButton ID="lnkView" Text="View in Browser" CommandArgument='' OnClientClick="window.document.forms[0].target='blank';" runat="server" OnClick="ViewFile" />     

我使用以下代码填充GridView：

 if (!Page.IsPostBack) { BindData(); //MessageBox.Show(files.Count() + ""); // displays the count for the files being displayed } protected void BindData() { try { filePaths = Directory.GetFiles(@"C:\PDFGenerate"); files = new List(); foreach (string filePath in filePaths) { files.Add(new ListItem(Path.GetFileName(filePath), File.GetLastWriteTime(filePath).ToString())); } GridView1.DataSource = files; GridView1.DataBind(); Session["fileData"] = files; } catch (Exception ce) { } //MessageBox.Show(files.Count() + ""); // displays the count for the files being displayed } 

我允许GridView中的排序方法，还添加了排序表达式。 我正在尝试编写允许排序的C＃代码，但我不确定如何使用它，因为我没有使用SQL数据源：

 protected void GridView1_Sorting(object server, GridViewSortEventArgs e) { switch (e.SortExpression) { case "FileName": if (e.SortDirection == SortDirection.Ascending) { GridView1.DataSource = Session["fileData"];//DO BY ASCENDING GridView1.DataBind(); } else { GridView1.DataSource = Session["fileData"];//DO BY DESCENDING GridView1.DataBind(); } break; case "FileDate": break; } } 

更新：我是如何让它正常工作的…

 protected void Page_Load(object sender, EventArgs e) { string strDirectory = @"C:\PDFGenerate\"; try { if (!Directory.Exists(strDirectory)) { Directory.CreateDirectory(strDirectory); } } catch (Exception ce) { //tc.Text = "Unable to create directory to save generated PDF files"; } if (!Page.IsPostBack) //loaded first time... { //MessageBox.Show("Fires from a PAGE REFRESH or FIRST VISIT"); BindData(); } else //loaded after an event (button click, link click, etc.) { //MessageBox.Show("Fires from an EVENT"); } } protected void BindData() { try { filePaths = Directory.GetFiles(@"C:\PDFGenerate"); files = new List(); foreach (string filePath in filePaths) { files.Add(new ListItem(Path.GetFileName(filePath), File.GetLastWriteTime(filePath).ToString())); } GridView1.DataSource = files; GridView1.DataBind(); Session["fileData"] = files; } catch (Exception ce) { } //MessageBox.Show(files.Count() + ""); // displays the count for the files being displayed } protected void GridView1_Sorting(object server, GridViewSortEventArgs e) { DataBind(); string strSortExpression = e.SortExpression; switch (strSortExpression) { case "FileName": if (e.SortExpression == (string)ViewState["SortColumn"]) { // We are resorting the same column, so flip the sort direction e.SortDirection = ((SortDirection)ViewState["SortColumnDirection"] == SortDirection.Ascending) ? SortDirection.Descending : SortDirection.Ascending; } if (e.SortDirection == SortDirection.Ascending) { //MessageBox.Show("ASC"); var dataTable = ToDataTable((IList)Session["fileData"]); var dataView = new DataView(dataTable); dataView.Sort = string.Format("{0} {1}", "Text", e.SortDirection == SortDirection.Ascending ? "ASC" : "DESC"); GridView1.DataSource = dataView; GridView1.DataBind(); } else { //MessageBox.Show("DESC"); var dataTable = ToDataTable((IList)Session["fileData"]); var dataView = new DataView(dataTable); dataView.Sort = string.Format("{0} {1}", "Text", e.SortDirection == SortDirection.Descending ? "DESC" : "ASC"); GridView1.DataSource = dataView; GridView1.DataBind(); } ViewState["SortColumn"] = e.SortExpression; ViewState["SortColumnDirection"] = e.SortDirection; break; case "FileDate": if (e.SortExpression == (string)ViewState["SortColumn"]) { // We are resorting the same column, so flip the sort direction e.SortDirection = ((SortDirection)ViewState["SortColumnDirection"] == SortDirection.Ascending) ? SortDirection.Descending : SortDirection.Ascending; } if (e.SortDirection == SortDirection.Ascending) { var dataTable = ToDataTable((IList)Session["fileData"]); var dataView = new DataView(dataTable); dataView.Sort = string.Format("{0} {1}", "Value", e.SortDirection == SortDirection.Ascending ? "ASC" : "DESC"); GridView1.DataSource = dataView; GridView1.DataBind(); } else { var dataTable = ToDataTable((IList)Session["fileData"]); var dataView = new DataView(dataTable); dataView.Sort = string.Format("{0} {1}", "Value", e.SortDirection == SortDirection.Descending ? "DESC" : "ASC"); GridView1.DataSource = dataView; GridView1.DataBind(); } ViewState["SortColumn"] = e.SortExpression; ViewState["SortColumnDirection"] = e.SortDirection; break; } } public DataTable ToDataTable(IList data) { var table = new DataTable(); table.Columns.Add("Value", typeof(string)); table.Columns.Add("Text", typeof(string)); foreach (var item in data) { var row = table.NewRow(); row["Value"] = item.Value; row["Text"] = item.Text; table.Rows.Add(row); } return table; } 

Answer 1

虽然不建议在视图的代码隐藏中放置逻辑，但您可以使用以下代码实现此目的：

 protected void GridView1_Sorting(object server, GridViewSortEventArgs e) { switch (e.SortExpression) { case "FileName": var dataTable = ToDataTable((IList)Session["fileData"]); var dataView = new DataView(dataTable); dataView.Sort = string.Format("{0} {1}", e.SortExpression, e.SortDirection == SortDirection.Ascending ? "ASC" : "DESC"); GridView1.DataSource = dataView; GridView1.DataBind(); case "FileDate": break; } } 

此外，请确保集合中的项目实现System.IComparable

最后，添加以下代码以将会话数据加载到dataTable中：

 public DataTable ToDataTable(IList data) { var table = new DataTable(); table.Columns.Add("Value", typeof(string)); table.Columns.Add("Text", typeof(string)); foreach (var item in data) { var row = table.NewRow(); row["Value"] = item.Value; row["Text"] = item.Text; table.Rows.Add(row); } return table; } 

Answer 2

要按照我之前的答案讨论中的要求对代码进行排序，请执行以下操作：

创建一个名为sort的方法：

 public void Sort(IList items, SortDirection direction) { var dataTable = ToDataTable(items); var dataView = new DataView(dataTable); dataView.Sort = string.Format("{0} {1}", "Text", direction == SortDirection.Ascending ? "ASC" : "DESC"); GridView1.DataSource = dataView; GridView1.DataBind(); } 

将BindData的实现更改为：

 protected void BindData() { try { filePaths = Directory.GetFiles(@"C:\PDFGenerate"); files = new List(); foreach (string filePath in filePaths) { files.Add(new ListItem(Path.GetFileName(filePath), File.GetLastWriteTime(filePath).ToString())); } Session["fileData"] = files; Sort(files, SortDirection.Descending); } catch (Exception ce) { } //MessageBox.Show(files.Count() + ""); // displays the count for the files being displayed } 

然后，将GridView1_Sorting更改为：

  protected void GridView1_Sorting(object server, GridViewSortEventArgs e) { string strSortExpression = e.SortExpression; switch (strSortExpression) { case "FileName": case "FileDate": if (e.SortExpression == (string)ViewState["SortColumn"]) { // We are resorting the same column, so flip the sort direction e.SortDirection = ((SortDirection)ViewState["SortColumnDirection"] == SortDirection.Ascending) ? SortDirection.Descending : SortDirection.Ascending; } Sort((IList)Session["fileData"], e.SortDirection); ViewState["SortColumn"] = e.SortExpression; ViewState["SortColumnDirection"] = e.SortDirection; break; } } 

Answer 3

您必须设置GridView属性：

 GridView1.AllowSorting="true" 

在后面的代码（Page_Load事件）或Page html中：其余部分详见http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.gridview.allowsorting%28v= vs.110％29.aspx