TableAdapter Update GridView

Hello,

I am trying to manually update a GridView row using TableAdapter.Update. I cannot use the object datasource.
I am able to fill the GridView, but when I call the update method, the error says that my datarow (id, etc) does not exist in the current context.

Below is my code. Does anyone know what am am missing or if my update statement is wrong. Thank you

partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e
{
     productTableAdapter pAdapter = new productTableAdapter();
     GridView1.DataSource = pAdapter.GetData();
    GridView1.DataBind();
}

protected void GridView1_RowEditing(object sender, GridViewEditEventArgs e)
{
GridView1.EditIndex = e.NewEditIndex;
}

protected void GridView1_RowUpdating(object sender, GridViewEditEventArgs e)
{
productTableAdapter pAdapter = new productTableAdapter();
GridView1.UpdateRow = pAdapter.Update(id = @original_id, name = @name, description = @description);
GridView1.DataBind();
}
}

<% @ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title></head><body>
<form id="form1" runat="server">
<div>
<asp:GridView ID="GridView1" runat="server">
<Columns>
<asp:CommandField ShowEditButton="True" />
</Columns>
</asp:GridView>
</div>
</form>
</body>
</html>

Re: TableAdapter Update GridView

Get the updated values from the GridViewEventArgs.NewValues property:

protected void GridView1_RowUpdating(object sender, GridViewEditEventArgs e)
 {
productTableAdapter pAdapter = new productTableAdapter();
int id = Convert.ToInt32(e.OldValues["id"]);
string name = e.NewValues["name"].ToString();
string desc = e.NewValues["description"].ToString();

pAdapter.Update(id, name, description);

GridView1.EditIndex = -1;

GridView1.DataBind();
    }

Re: TableAdapter Update GridView

Hello mm10,

Thanks for repying.

I tried this method, but it throws a new error: CS0117: 'System.Web.UI.WebControls.GridViewEditEventArgs' does not contain a definition for 'OldValues'. When I take out that line, it tells me that no definition is contained for NewValues.

Any clues? I'm not sure how to go about defining these.

Thankyou

Re: TableAdapter Update GridView

Oh, you should use the GridViewUpdateEventArgs:

protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
{
productTableAdapter pAdapter = new productTableAdapter();
int id = Convert.ToInt32(e.OldValues["id"]);
string name = e.NewValues["name"].ToString();
string desc = e.NewValues["description"].ToString();

pAdapter.Update(id, name, description);

GridView1.EditIndex = -1;

GridView1.DataBind();
}

Re: TableAdapter Update GridView

Thanks again, for replying

Now, however, I am getting this error: Object reference not set to an instance of an object: string name = e.NewValues["name"].ToString();

I've changed my HTML to this:

<asp:GridView ID="GridView1" runat="server"
AutoGenerateEditButton="True"
OnRowEditing="GridView1_RowEditing"
OnRowCancelingEdit="GridView1_RowCancelingEdit"
OnRowUpdating="GridView1_RowUpdating"></asp:GridView>

to eliminate a row editing not handled error,

and changed the update parameter slightly to eliminate the decsription not defined error:
this line: pAdapter.Update(name, desc, id);

I've also added a row cancelling event and the cancel event works, but it still throws the above error (Object reference not set to an instance of an object: string name = e.NewValues["name"].ToString(); when I click on edit

I still seem to be missing something..do you have any ideas?

Thanks for your replies

Re: TableAdapter Update GridView

Do you have a column in the GridView bound to a field called "name"? If you don't, you have to change "name" to the name of the bound field holding the name value.

Re: TableAdapter Update GridView

yes, I do. The bound columns are name and description..and id.

thanks. Thought maybe the gridview is empty when I click on edit or it is not finding the id..not really sure if I need a session object tied to the populated gridview..seems like I have tried everything..but no luck yet

thanks

Re: TableAdapter Update GridView

Set a breakpoint in the method and find out how many keys there are in e.NewValues.

Re: TableAdapter Update GridView

Hello liza99

Solutions

Create an ObjectDataSource+TableAdapter to expose CRUD methodsand bind to the GridView by enabling its CRUD functions

Reasons

If you create a new instance of TableAdapter from time to timeI think it cannot "remember" what it used to haveSo there will be confliction when rendering the pageSo you need a "consistance" TableAdapterwith a table insideSo ObjectDataSource is better

Re: TableAdapter Update GridView

Thanks mm10,

It appears that the values are empty, but I acnnot figure out why. Thanks for replying.

Re: TableAdapter Update GridView

Thanks Decker for replying,

I have another version of the project with object data source, which works ok, but I really need to update more that one table at a time,
that is why I am trying to using the row updating and programmatic binding. Do you know of a way to update more that one table with object data source; I didn't think it was possible? I will eventually have item template columns in gridview which call from a second table adapter, although can't say it's going well so far...

Re: TableAdapter Update GridView

liza99
I really need to update more that one table at a time,

Just use Stored Procudre instead of a pure SQL statement or use something like Trigger to update related tables at a time

Re: TableAdapter Update GridView

liza99

Thanks mm10,

It appears that the values are empty, but I acnnot figure out why. Thanks for replying.

Get the values from the controls in the GridView then:

protected void GridView1_RowUpdating(object sender, GridViewUpdateEventArgs e)
 {

GridViewRow row = GridView1.Rows[e.RowIndex];
int id = Convert.ToInt32(row.Cells[0].Text); // if id is a readonly field in your GridView
string name = ((TextBox)(row.Cells[1].Controls[0])).Text;
string desc = ((TextBox)(row.Cells[2].Controls[0])).Text;

productTableAdapter pAdapter = new productTableAdapter();
pAdapter.Update(id, name, description);
 
GridView1.EditIndex = -1;
 
GridView1.DataBind();
    }

Re: TableAdapter Update GridView

thanks, still get Input string was not in a correct format for any line when clicking update

Id is read only, primary key, autoincrement, still seems to be coming up NULL; there is data there

rechecked all data types...match in database, table adapter, code behind...

still trying things to no avail

Re: TableAdapter Update GridView

Hello liza99

Plz set "DataKeyNames" property for the GridViewAnd then generate CRUD methods for the TableAdapter and bind it with ObjectDataSource to the GridView

Re: TableAdapter Update GridView

liza99

thanks, still get Input string was not in a correct format for any line when clicking update

Id is read only, primary key, autoincrement, still seems to be coming up NULL; there is data there

rechecked all data types...match in database, table adapter, code behind...

still trying things to no avail

Is the id shown in the FIRST column of your GridView?

Re: TableAdapter Update GridView

yes, id is in the first column. I've also tried moving it around, but no good results

Re: TableAdapter Update GridView

What's the value of row.Cells[0].Text and row.Cells[1].Controls.Count inside the RowUpdating event? Debug in Visual Studio to find out.