【发布时间】：2014-06-30 13:55:40
【问题描述】：
我有以下 GirdView，它显示一些文件及其修改日期：
<asp:GridView ID="GridView1" AllowSorting="true" OnSorting="GridView1_Sorting" ClientIDMode="Static" runat="server" AutoGenerateColumns="false" EmptyDataText="No PDF was generated">
<Columns>
<asp:BoundField DataField="Text" HeaderText="File Name" SortExpression="FileName" />
<asp:BoundField DataField="Value" HeaderText="File Date" SortExpression="FileDate" />
<asp:TemplateField>
<ItemTemplate>
<asp:LinkButton ID="lnkDownload" Text="Download" runat="server"
CommandArgument='<%# Container.DataItemIndex %>'
OnClick="DownloadFile" />
</ItemTemplate>
</asp:TemplateField>
<asp:TemplateField>
<ItemTemplate>
<asp:LinkButton ID="lnkView" Text="View in Browser"
CommandArgument='<%# Container.DataItemIndex %>'
OnClientClick="window.document.forms[0].target='blank';"
runat="server" OnClick="ViewFile" />
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
我正在使用以下代码填充 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<ListItem>();
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
}
我在 GridView 中允许了排序方法，还添加了排序表达式。我正在尝试编写允许排序的 C# 代码，但我不确定我将如何处理它，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<ListItem>();
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<ListItem>)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<ListItem>)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<ListItem>)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<ListItem>)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<ListItem> 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;
}
【问题讨论】：
-
对您的数据源进行排序并将其反馈回您的网格。有什么问题？
-
我更新了我的问题以包括我的数据源是什么。它们是文件夹中的文件。
-
我更新了我的问题。 GridView 在一列中显示文件名，在另一列中显示来自指定文件夹的文件修改日期。我想让用户使用文件名或文件日期对每一列进行排序。
-
但在 GridView1_Sorting 事件中分配给 gridview 之前，我没有看到 Session["fileData"] 上发生排序。您是否尝试将 Session["fileData"] 转换为相关类型并使用 LINQ 进行排序，然后分配给 GridView？
-
我不知道如何实现...