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Checkbox control in gridview

I have a gridview with checkbox control as a template field and one bounded field..
The grid is binded on every postback through a function and the grid contents remain the same on every post back..now when i check one of the checkboxes and then click the button at the end of the page, I need to store that particular row information..but I'm not able to retreive that information because when I check and then click button..the page loads and then the grid again populates and then checkboxes become uncheck and no CheckedChanged event fires..Help me with this
I need to persist the state of checkbox on every postback even when it is checked..how to do this??

In the page_load event function, please use the following code for your persistent data
if (!IsPostBack)
{
//your static data
}

This particular problem is fairly common. I haven't seen any "simple" solution yet, but here are 3 separate methods I have used. Each was used because of a limitation in the system.
Solution 1
Use AJAX. By putting your controls within an update panel, you can persist the changes by making them "real-time" in the database. This is not really a "simple" solution, but in my opinion it is one of the easiest to implement. Since the change is psuedo-immediate, there is no real need to worry about post-backs and persistence.
Solution 2
Use a "change management" control of sorts. You can apply a hidden control whose value is used to keep track of any changes made in relevant controls. You would need to devise a coherent data structure that provide at least a control ID and the new value (possibly the old value if you need some kind of "roll-back" feature). This would need to be coded in JavaScript so that any changes to the hidden control's value were structured and not duplicated. Then on your postback you would need to read this control's value, make any pertinent changes, and then rebind your data as appropriate. This can be fairly cumbersome, and it would need to be well-documented in the event that you pass this application on to a successor.
Solution 3
Use the PostBack for CheckChanged events and keep all data managed in the view state. During the RowItemCreated event of the GridView you can find the checkbox control in the relevant cell and manually add the delegate handler to that control to handle the postback in the event of a CheckChanged event firing. You can then have the change immediate. The drawback to this is that PostBack events become frequent and heavy. If you're storing large amounts of data in the ViewState this also causes page load to be slow and unresponsive, so whatever structure you choose for the ViewState you'll want to keep it small.

This is possible if you are using asp.net 4.0 using
<asp:GridView id="GridView2" runat="server" EnablePersistedSelection="true">
</asp:GridView>
If you are using 3.5, you will have to retain checkbox info in viewstate. I hope this will be helpful.
http://www.codeproject.com/Articles/202938/How-to-select-multiple-records-from-the-GridView-a
Another Option:
This is how msdn have described a hotmail type gridview.. may be this can help.. this will require you to extend existing GridView Control.
http://msdn.microsoft.com/en-us/magazine/cc163612.aspx
Regards.

Checkbox.checked in gridview on postback

I have a gridview with checkbox in Itemtemplate. What i need to do is check the condition:
(checkbox.checked==true)
if its true take the rows to another gridview. i binded the data of the gridview in
if(!PostBack)condition.
Everything was working fine until my employer said he doesnt wants the gridview to be bound in the if(!postback) condition but if i take that condition out checkbox.checked value is false always!

From the details of your question, I'm not sure if your boss wants the grid unbound or doesn't want the page bloated with the grid's ViewState, but in my experience, it's usually the latter. However, if your boss simply doesn't want the grid bound in the "if(!Postback)" condition and doesn't mind if it's bound or uses ViewState, then your boss doesn't understand web development using C# and server-side controls.
But... to answer your question, the reason the checkboxes are all unchecked is because you're rebinding the grid AFTER the ViewState has been applied. ViewState contains all the data needed in a postback condition to set the state of the checkboxes during postbacks and applies that data prior to the OnLoad (or Page_Load) event. By rebinding the grid, you are essentially wiping out anything that was posted back in ViewState and applied. To overcome this, turn ViewState off for the grid and apply the state of the checkboxes yourself AFTER you rebind the grid using the FORM collection.
If you want to do away with ViewState, here are some tips in this article.
http://www.codeproject.com/KB/viewstate/DataGridViewState.aspx

ASP.NET GridView binding sequence

I'm trying to bind my GridView at runtime, but I'm also trying to avoid running all the binding events twice.
I have a GridView that gets populated from a function that returns a DataTable. I'm not using ViewState in the grid for a couple of reasons. I seem to have a Catch-22 situation here:
If I don't bind the grid by Page_Load at the latest, the RowCommand and other grid events won't fire.
If I DO bind the grid in Page_Load, but I'm on a PostBack from a pager link, sort link, or search button, those event handlers will change the data and need to rebind it, running all the binding code again.
The grid triggers DataBound, RowDataBound, and RowCreated events, which could be performing expensive operations. I really hate to call them all in Page_Load, and then wipe out the data and call them all again if the data changes. But I can't seem to avoid this double duty, because in Page_Load I don't know if it was a grid event that will change the data, or a grid event that doesn't.
Any ideas?

Try the command arguments. If a button in the gridview was clicked, that event will be fired and you can handle it appropriately. Your question is not clear enough i'm afraid. Could you be more specific?

Check if request is a postback. Bind the datatable to the grid like so:
If(!ispostback)...
That way you wont be binding the table to the grid on each request.

UpdatePanel does full postback first time

I have a custom control that has an update panel in it. Within the update panel, there are no custom controls, but there are custom controls outside the update panel. All controls have an ID set as do the parents of the controls. Inside the update panel is a repeater that has controls that should trigger an async postback. The update panel has an update mode of conditional and children as triggers is off. The update panel renders standalone divs, not table cells. EnablePartialRendering is on on the script manager.
Each repeater item has numerous textboxes, but two of them have autopostback turned on. Inside the repeater ItemDataBound event, I register the control with the script manager's RegisterAsyncPostBackControl.
If I edit either textbox, it does a callback correctly. But after the first one is edited, if you edit the other one, it does a full postback. It doesn't matter which one is done first. But after it's done its postback, if you edit either of the textboxes, it does callbacks correctly.
I've tried several things like changing the UpdateMode and ChildrenAsTriggers properties to various combinations. Nothing seems to work.
Any suggestions?

A lot of things can cause this, compare UpdatePanel causes full page postback with LinkButton in ListView in UpdatePanel causes full postback.
You'll need to provide more information, e.g. .NET Framework version, IIS version etc. exact ASP.NET markup etc
But since you asked for "Any suggestions?" try looking through these questions

Gridview, is there an event, how would I determine that it has finished being rendered?

Gridview, is there an event, how would I determine that it has finished being rendered? That's basically it, I want to adjust the height of some other controls on the page and I want to pick up this event.
Sorry I should have been more explicit in stating that this is actually a web page not a winform. In the end I managed to solve the problem by registering a function with the page load which is called after the controls have been drawn and they calling the gridview size and resizing the other controls to fit. It works and that is that.
Thanks.

The GridView inherits from Control so you can use any of the events, I would try PreRender, it seams it will provide you with what you need

To see all the GridView events available to you;
In Design Mode, select the gridview and click F4.
In the properties window there is a 'lighting' tab which lists all gridview events you can attach to.

Assuming you are in winforms, the best place to do it would be after you bind data to your grid, in the DataBindingComplete event.

Managed to solve it, see details above.