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I would sincerely appreciate it if someone could explain the following issue experienced w/ 2 different methods of GridView creation for an ASP.NET 2.0 page.  In the following code snippet taking from one of my .aspx files I create a GridView bound to the ObjectDataSource shown.  That ObjectDataSource is bound to a BL layer class and method that simply returns a DataTable object (SelectMethod="getSysDataTable").  Paging and Sorting are set to True and each of those functions works perfectly.  In the code-behind file for this .aspx file there is no code or events written for the GridView (no paging or sorting event handlers), just a few button and text box handlers on that page that are needed.  The paging and sorting of the presented data works w/o any issue. 

   BorderStyle="Solid" BorderWidth="1px" CellPadding="3" ForeColor="Black" GridLines="Vertical" AllowPaging="True" AllowSorting="True" EmptyDataText="No records found"
 PageSize="5" >
 
       DataTextFormatString="Select" HeaderText="Edit" />
    
    
  
 
 

On another .aspx page however, I am doing a similar GridView w/ an ObjectDataSource only it is done in a slightly different manner

   BorderStyle="Solid" BorderWidth="1px" CellPadding="3" ForeColor="Black" GridLines="Vertical" AllowPaging="True" AllowSorting="True" EmptyDataText="No records found" PageSize="5">
 
       DataTextFormatString="Select" HeaderText="Edit" />
    
    
    
    
    
    
 
 .

Note the main difference (aside from the bound columns) - no ObjectDataSource is specified on the .aspx page hence the DataSourceID property of the GridView is not set yet.  However, now in the .aspx.cs code-behind for this page, I do the following:

 protected void Page_Load(object sender, EventArgs e)
 {
  if (!Page.IsPostBack)
  {
      BindData();
  }
 }   

 private void BindData()
 {

  ObjectDataSource obds = new ObjectDataSource();
  obds.TypeName = "BatchSummaryVwDAO";  // again a simple BL class that calls an external API that returns a typed Array[] of objects.
  obds.SelectMethod = "getBatchSummaryDataTable"; // a method on that class that then returns a DataTable object created from the typed Array[] of objects.
  obds.DataBind();
  GridViewMonitor.DataSource = obds;
  GridViewMonitor.DataBind();
 }

 The page renders fine initially w/ the GridView data displayed - but if I attempt to "page" by clicking the paging control or "sort" by clicking one of the column header titles, I get unhandled Exceptions thrown stating either:

 GridViewMonitor fired event PageIndexChanging which wasn't handled

 or

 GridViewMonitor fired event Sorting which wasn't handled.

The BIG QUESTION - why in the first scenario does paging and sorting work w/o having to write handler logic for each yet in the second scenario, you get these exceptions.  It seems that I am wiring everything together and binding to DataTables the same way...in one case "declaratively" in the aspx page and in the other programmatically in the .aspx.cs code-behind.  Any advice would be really appreciated.

Thanks in advance

I was also getting the Your gridview xxx "fired event Sorting which wasn't handled"

It took hours to find the fix.

I found this on the Microsoft page about the GridView class: http://msdn2.microsoft.com/en-us/library/system.web.ui.webcontrols.gridview(VS.80).aspx

=======================

Binding to Data

The GridView control can be bound to a data source control (such as SqlDataSource , ObjectDataSource , and so on), as well as any data source that implements the System.Collections.IEnumerable interface (such as System.Data.DataView , System.Collections.ArrayList , or System.Collections.Hashtable ). Use one of the following methods to bind the GridView control to the appropriate data source type:

 =============================

The DataBind() method DOES NOT provide built-in sorting, updating, deleting and paging!

 Hope this helps.

 - bob archer