Develop Reference

Sorting gridview clears gridview when databinding from code behind

I have an ASP.net C# page that uses a stored procedure in a single SQL query to return multiple tables.
I then bind each GridView in the page to the corresponding table from the query:
grdCustomers.DataSource = objDS.Tables[3];
grdCustomers.DataBind();
This works well but clears out the data when you sort the GridView columns. I understand I need to bind the data again on post-back but I'm not sure of an easy way to do this since the GridViews are not bound on page load now.
What's the easiest way to keep the GridView binding on sort as well as sort the columns correctly when binding the data in code behind?

How get a new datatable after reordering the gridview

I populate a gridview from the db.
then i re arranged the rows in the gridview with javascript code.
i want to copy the rearranged gridview to a datatable
how it possible??

If you re-arranged your data using Javascript, you will have to update the database using Javascript. You will not be able to do if using server-side code.
Getting data and binding a GridView on the server-side and then rearranging it with Javascript is not a good idea. I suggest you either get your data purely from Javascript, or arrange your data on the server side before binding your GridView.

There could be multiple methods
First method
GridView row would have a hidden field in each row which should be updated with new row index and have a column for row index / order in database.
When user changes the row index of GridView Row, you will have to change the hidden fields of all effected with new rowindex. On server side you will have to iterate through the GridView rows and save the respective rows index / order in row column for order of row.
Second Method
You can send the changed rows index on each arrangement using the ajax (jquery ajax) and save the changed index in database row order column.

if you need to sort the gridview without reloading the page , then use an update panel enable and code for gridview pageindexchanging and sorting event , if you need any indication while processing use an updateprogress control .
If you are intended to update the data . then use ajax to send the data to a webmethod and update it into DB

How to create a gridview in asp.net having features similar to the datagridview in Windows forms

I understand that the Gridview of asp.net and windows forms are different, but my requirement is that I have a registration form where in a user registers his vehicles.
A single user can have many vehicles, so I want to provide a Gridview with the column names specified and allow users to enter the values in the rows. Depending on the number of vehicles, the user keeps adding them. This task is actually easy in the Windows forms since the grid is in such a way that an empty row is provided by default and we can type in the cells. Finally we can read the DataGridview by each row and save the results to database.
I am looking for this feature in the Asp.net either with the Gridview or any other data control. This looks pretty complex with the asp.net gridview since ill need to work with the edit button, update button for doing this every time and also a add new row button every time.
Is there any other way I can do this task without complexity. I am fairly new to asp.net.

If you want to add a new row then what you can do it add a footer row to the gridview. and everytime the user enter information in the footer row you can bind it to gridview and when the page is reloaded you will always have the footer row. This way user can register as many cars they want.

GridLookUpEdit and Multi-part Keys

I realize that the DevExpress GridLookUpEdit editor was not designed to work with data that has multi-part keys. However, I am trying to workaround this limitation anyway.
The data for my GridLookUpEdit is Product-Purity with two columns "PRODUCT_ID" and "PURITY_ID". I have this code to set the purity of the underlying grid when the user selects the product-purity row in the GridLookupEdit:
void lookUpEditProductPurities_EditValueChanged(object sender, EventArgs e)
{
// Get the purity from the product selected and update the purity column of the grid.
DevExpress.XtraEditors.GridLookUpEdit editor = (sender as DevExpress.XtraEditors.GridLookUpEdit);
DevExpress.XtraGrid.Views.Grid.GridView view = editor.Properties.View as DevExpress.XtraGrid.Views.Grid.GridView;
object val = view.GetRowCellValue(view.FocusedRowHandle, "PURITY_ID");
if (editor.Parent is GridControl)
{
GridControl ParentGridControl = (editor.Parent as GridControl);
GridView ParentGridView = (ParentGridControl.MainView as GridView);
DataRow CurrentDataRow = ParentGridView.GetDataRow(ParentGridView.FocusedRowHandle);
CurrentDataRow["PRODUCT_PURITY_ID"] = val;
}
}
This works fine when I use it from a master grid, with one small problem. When an existing row refers to a purity that is not the first purity for a product, popping the grid will make it appear as though the first purity is selected. This is not a big deal as far as I am concerned.
However: the big problem I am having is when I use this GridLookUpEdit in a detail row of a master-detail grid. The call: editor.Parent is returning the grid control for the master and ParentGridControl.MainView is returning the GridView for the master.
How do I get at the gridView that the GridLookUpEdit is an editor for - the child gridView??
tia -

Your task (getting a detail view) can be implemented using the approach shown in the What can cause the properties, methods, and events of a detail grid view to fail? article - use the
GridView.GetDetailView method.
Please also review the following article:
Navigating Through Master and Detail Rows

Adding rows to a table based on user input (ASP.NEt)

I have a TextBox entry field where the user will enter a integer value. And then there is a "Create" button, which when clicked upon must generate a Table with 2 columns :
"Name" and "Email" being the column headers.
I want each row to have a textbox in each of these columns.
All of this has to happen after the button is clicked. I have discovered that if you dynamically add a control in ASP.NET(I am using C#) then the controls are lost during postback. And I don't know how to prevent that from happening.
Can somebody please give me some ideas regarding how to go about adding rows dynamically to a table (I tried using the asp.net Server side table control but ran into the "lost-during-postback" problem - can I try with something else like a gridview ? but afaik a GV will not work without data bound to it )
Point to note is that my table has textboxes for user entry and it is not for showing data ..rather it is for accepting data from the user which will be later used to persist details to the database.

Dynamic Controls
That's involved. Here's an interesting article on the issue of dynamic controls.
I think normally if you create dynamic controls then you're responsible for recreating them on postback; however the article contains a way to use the Init event if it's copacetic with your app.
Edit:
or Regular ASP.NET Controls
You can use data bound ASP.NET controls like: DataList, Repeater, GridView, etc. (You can put text boxes and all other kinds of controls into them for repeating in each row - or "item") and bind values to it. If you need to perform some processing on the user input first, then generate an internal Array, List, Dictionary, DataTable etc. (your choice) and bind that data as a data source to the ASP.NET control of choice.
aspnetControl.DataSource = myDataTable;
aspnetControl.DataBind();
or
aspnetControl.DataSourceId = "name_of_control";
There are various ways to assign a data source.
This way you won't run into the same problems as with dynamic control creation; however there is a lot to learn to facilitate this way too.