Can someone share how to practically implement gridview sorting and handle that event if:
- The data is binded manually
- Gridview is built using template field that is pumped from code behind only (not from the markups)
I build my gridview solely from codebehind therefore I can't use the default method or solution.
Thank you
This might be what you are looking for:
protected void GridView1_Sorting(object sender, GridViewSortEventArgs e)
{
listBindByName(); //this would be your procedure to look for the data you want
DataSet dsSortTable = GridView1.DataSource as DataSet;
DataTable dtSortTable = dsSortTable.Tables[0];
if (dtSortTable != null)
{
DataView dvSortedView = new DataView(dtSortTable);
dvSortedView.Sort = e.SortExpression + " " + getSortDirectionString();
ViewState["sortExpression"] = e.SortExpression;
GridView1.DataSource = dvSortedView;
GridView1.DataBind();
}
UpdatePanel1.Update();
}
private string getSortDirectionString()
{
if (ViewState["sortDirection"] == null)
{
ViewState["sortDirection"] = "ASC";
}
else
{
if (ViewState["sortDirection"].ToString() == "ASC")
{
ViewState["sortDirection"] = "DESC";
return ViewState["sortDirection"].ToString();
}
if (ViewState["sortDirection"].ToString() == "DESC")
{
ViewState["sortDirection"] = "ASC";
return ViewState["sortDirection"].ToString();
}
}
return ViewState["sortDirection"].ToString();
}
This is an example of the TemplateField:
<asp:TemplateField HeaderText="Description" SortExpression="description">
<ItemTemplate>
<asp:Label Visible="true" runat="server" ID="descriptionLabel" Text='<%# bind("description") %>'></asp:Label>
</ItemTemplate>
<EditItemTemplate>
<asp:TextBox ID="txtEditDescription" Width="100px" runat="server" Text='<%#Bind("description") %>' />
</EditItemTemplate>
</asp:TemplateField>
By adding the SortExpression property the GridView header will become clickable. Make sure the sort expression attribute is the name of the field that you are binding through the sql query.
Hope this helps.
/* Best to use the shortened routine below - which can be further shortened */
private string GetSortDirectionString()
{
if (ViewState["sortDirection"] == null) ViewState["sortDirection"] = "ASC";
var currDir = ViewState["sortDirection"].ToString().ToUpper();
switch (currDir)
{
case "ASC": ViewState["sortDirection"] = "DESC"; break;
case "DESC": ViewState["sortDirection"] = "ASC"; break;
}
return ViewState["sortDirection"].ToString();
}
Grid view Sorting In asp .net
Step ONE Add grid view to your page edit the source code by adding allow sorting true and initiating an event by on sorting
<asp:GridView ID="GridView1" AllowSorting="true" OnSorting="GridView1_Sorting" runat="server">
</asp:GridView>
Step Two
In the code behind page..we need to handle this event "GridView1_Sorting" and the data table binding. On page load we will bind the datatable with the gridview
dt = Class1.getDataSet().Tables[0]; // here dt is the datatable object declared Globally.
GridView1.DataSource = dt;
GridView1.DataBind();
so now if we run our code the grid view will be visible but no sorting.
Step Three
Next we need to handle the Gridview Sorting Event. First of all we need to declare one static string SortDirection.
protected void SetSortDirection(string sortDirection)
{
if (sortDirection == "ASC")
{
_sortDirection = "DESC";
}
else
{
_sortDirection = "ASC";
}
}
so the sortDirection is a static string...This function we used to switch between ascendin and descending... Step 4
protected void GridView1_Sorting(object sender, GridViewSortEventArgs e)
{
SetSortDirection(SortDirection);
if (dt != null)
{
//Sort the data.
dt.DefaultView.Sort = e.SortExpression + " " + _sortDirection;
GridView1.DataSource = dt;
GridView1.DataBind();
SortDireaction = _sortDirection;
}
}
so we have completed our sorting.... sortExpression is nothing but the column name...
