Develop Reference

Gridview returning empty even when there is data. I want to use data in the gridview to update another database

I have a webform that the user captures data. This data affects other data that is in a Gridview. I wanted to right a DetailsView type control that makes an Update button visible if data is change in textboxes and drop downs that would require a master data update.
I have a gridview on the form and when the user click on update I wanted to update all the rows in the databases using the primary key OrderId which is on the Gridview.
If I put the code being each textbox and dropdown box and that calls a routine called DoUpdate then this works. However it is a little slow since each change forces an update, so I thought it would be better to rather have an update button appear, and then the user can click that to do the update.
When the routine is called from the button routine though the gridview has no rows. I assume I either need to findcontrol (gridview) or something but have not idea what to find it in.
Here is the code that works when called in a behind button event, but the gridview returns row count 0 when called as part of the code behind button:
List<string> _OrderIds = new List<string>();
foreach (GridViewRow gvr in gvOrderLines.Rows)
{
Label myOrderIDLablel = (Label)gvr.FindControl("lblOrderID"); //find control since it is a template field
_OrderIds.Add(myOrderIDLablel.Text);
}
The gridview is defined in the ASP page
<asp:GridView ID="gvOrderLines" runat="server" AutoGenerateColumns="False"
DataSourceID="odsOrderDetail"

Per my comment above you may want to do something like:
List<string> _OrderIds = new List<string>();
DataTable table = gvOrderLines.DataSource as DataTable;
foreach (GridViewRow gvr in table.Rows)
{
Label myOrderIDLablel = (Label)gvr.FindControl("lblOrderID"); //find control since it is a template field
_OrderIds.Add(myOrderIDLablel.Text);
}
I hope this get you headed in the right direction.

How to remove the clickevent of the Gridview in c# asp.net

I have a gridview with OnRowDataBound method to manually create dynamic divs in the cells within a column. I use .Attribute.Add("onmouseover","DisplayData( .... )") to add mouseover events on the cells.
At run time when one of the cells is mouseovered it invokes an AJAX function to retrieve data, which in turn populates the div inside the cell. That data contains hypelinks. The problem is, those hyperlinks are not clickable because they are overridden by the click event of the Gridview.
How can I remove the clickevent of the Gridview so it would not interfere with my AJAX-built hyperlinks within the divs that are inside the Gridview?

Color updated Grid View cells in asp.net

I am creating one web application in ASP.NET. What I want is when the invoice is created and when the quantity or amount is changed in the GridView then the rows effecting that GridView cell should get a highlighted color for some seconds and then get back to normal as they were.
I just want to catch the eye of the user that the values changed.

It appears that you want a variation of the answer to this question:
How to change the gridview row colors in onclick event in javascript?
Rather than binding to the entire row, you would want to add the javascript function to an event associated with the quantity and amount field:
e.Row.Cells(x).attributes.add("onblur", "ChangeRowColor(this)");
Note: be careful here as onblur wont handle all changes. You might want to review Detect all changes to a <input type="text"> (immediately) using JQuery to detect all changes to your field.
Then in order to make your row "highlighted" you would find it easiest to use jQuery's Highlight effect.

Display ASP.NET GridView inside a selected row in another GridView

I have been given a mockup that I do not know is possible to code in ASP.NET without being a real html and javascript wizard.
I want a GridView that when a row is selected, the selected row expands and below the selected row a panel of additional information is shown, which would also include another small GridView. The idea is this would all be in-line. So if the user selected row 4, then the additional information would appear below row 4 and then after the additional information the parent GridView would continue with row 5.
Ultimately I would want to do a multi-select type of set up, but first I need to figure out if this is even possible. Also, the solution must be 508 Compliant
The one solution I considered was using only one "column". Then I would put all my fields in the ItemTemplate, and my detail panel content in the EditItemTemplate and instead of selecting the row, set it to edit mode. The problem with this solution is I lose the functionality of multiple columns if I throw everything in one huge ItemTemplate.
Any and all suggestions or ideas are appreciated.

What you're describing would be best fulfilled with a ListView control. It takes a little more templating work to set up than a grid view, but you have much more control over it and you can emulate the look of a GridView. You would set your Selected Item template to contain another ListView (or GridView) thats bound to your detailed data.

I've done this using a gridview inside a ListView and using ajaxcontroltoolkit collapsible panel
Your parent list would be a listview that would have 2 table rows for each item, on the first row your parent column, on the second row use colspan and add a gridview wrapped on a collapsible panel

edit datagrid row

i want to know how to edit a single row (which i select) from a data grid
for example i have a datagrid with columns A, B and C
and i have a couple rows of data, approx 10 rows.
lets say i want to change the value of data within row 4.
how would i do this?
i am using visual studio 2003, but i guess if visual studio 2005 would be okay too. for the coding I'm using c#
thanks..

All grid-like components of asp.net have the same machanism as it comes to starting to edit a single row. Actually it's default for asp.net only to edit a single row in a grid.
Needed to start editing is to include asp:button or asp:linkbutton in the ItemTemplate with the CommandName set to "Edit". This one of reserved commandnames all grid-like components knows how to respond to. Clicking this button in DataGrid will raise the EditCommand Event. In this event you have to set the EditItemIndex of the grid equal to Item.Itemindex of the eventargs. This will render the row vaccordeing to the EditItemTemplate.
In this template you put 2 buttons or linkbuttons. One should have the CommandName set to "Update" and one should have the CommandName set to "Cancel".
The "Update" button raises the UpdateCommand event. In which you execute code that store the data in the row to its storage (eg.: database) and sets the EditItemIndex to -1 --> all rows are rendered read-only(ItemTemplate or AlternateItemTemplate).
The "Cancel" button raises the CancelCommand event. In the event handler you have to do si set the EditItemIndex to -1.
This description is only true for DataGrid en not for the in asp.net introduced GridView which handles most of this "Boilerplate"code it self working together with the datasource controls. Google the web for more info on this. it's to much to explain here right now.
Hope it helps?

Take a look at the documentation for adding an EditItemTemplate to your datagrid. You use the ItemTemplate for view-only, display elements and you use the EditItemTemplate for controls used to bind against a single row that you select.
Here's a link that might help:
http://www.gridviewguy.com/

Is your data in a DataTable before making it a DataGrid, or can you put it in a DataTable? You can update/delete/edit rows in a DataTable, here's a link with code snippets, pretty straight forward:
http://msdn.microsoft.com/en-us/library/tat996zc(VS.80).aspx