Can somebody suggest to me, how to do it? If you don't want to use a BindingSource then you will need to tweak the code. Form code which handles detection of the CheckBox cell changes via mouse or keyboard.
As mentioned below I used mocked data. Please remember to mark the replies as answers if they help and unmark them if they provide no help, this will help others who are looking for solutions to the same or similar problem. VB Forums - moderator. That example is not working.
Because instead of updating a single record, it is updating all the records. Since my database is on cloud and it is multi user application. The content you requested has been removed. Ask a question. If you are using TemplateField columns then using. Text will give you an empty value. Instead you would need to use FindControl method to get the specific control that you want to access.
Here's a quick example:. PS: You may want to look at the following links below for implementing an edit,update and delete in gridview. Note that the examples are using DataTable as the datasource but it should help you how to setup editing,updating and deleting of rows :. You'll have to setup an Update method for you to extract the values and save it to your database. The error seems very logical. Make you that your method UpdateTableInfo has the following update parameters mentioned in the error.
You don't need to call "return" because once it goes inside your if! Also, I will do some validation, if it does not fulfil, i will need to return and display an error msg. I didn't say you do a direct. These tutorials strive to remove any control-level style settings, instead using cascading style sheets defined in an external file whenever possible.
The Styles. If we set these CssClass properties at the Web control we'd need to remember to explicitly set these property values for each and every data Web control added to our tutorials. A Theme is a collection of control-level property settings, images, and CSS classes that can be applied to pages across a site to enforce a common look and feel. A Skin is a file that defines the default properties for a Web control. Start by adding a new Skin File to your project named GridView.
Since we don't yet have such a folder, Visual Studio will kindly offer to create one for us when adding our first Skin. Next, enter the following markup into the GridView. Let's add another Skin for the DetailsView, a data Web control that we'll be using shortly. A Theme can be applied on a page-by-page basis or for all pages in a website.
Let's use this theme for all pages in the website. To accomplish this, add the following markup to Web. That's all there is to it! The styleSheetTheme setting indicates that the properties specified in the Theme should not override the properties specified at the control level. To specify that Theme settings should trump control settings, use the theme attribute in place of styleSheetTheme ; unfortunately, Theme settings specified via the theme attribute do not appear in the Visual Studio Design view.
Refer to ASP. NET Themes for more on configuring a page to use a theme. The GridView displays one row for each record returned by the data source control to which it's bound. There are times, however, when we may want to display a sole record or just one record at a time.
You can think of the DetailsView as a GridView with a single record rotated 90 degrees. The only difference is that the DetailsView's BoundFields are laid out horizontally rather than vertically. Figure 14 shows the DetailsView after its BoundFields and CssClass properties have been configured to make its appearance similar to the GridView example.
In the designer, delete airplaneBindingSource , and the controls will suddenly be unbound again. Note that we have to define our own BindingSource because we deleted the one in the designer. Anyway, run the program, and you should get the same thing as before:. Again, the DataGridView knows it can't create a column for Airplane.
This was easier than using the wizards, wasn't it? With only five more lines of code, you no longer need to set it up in the designer. On the other hand, the designer makes it easier to customize the columns. An interesting thing I've noticed about data binding is that it's fairly forgiving about the order in which you do things. Another interesting thing is that we don't have to tell BindingSource what kind of objects it will hold: you can take out the assignment to DataSource and the DataSource will stay equal to null , but internally, the BindingSource will still record the fact that the first object was an Airplane.
If you then add a non- Airplane to it, it throws InvalidOperationException. By the way, DataSource is a weird property. Instead of typeof Airplane , you could set it to an Airplane instead. Can you guess what happens if you replace the three Add statements with this? Spoiler: you'll end up with two airplanes, the Airbus and the Cessna. It's almost as though you had written:. By the way, if you modify txtModel.
Text in code, the Model of the current Airplane is not updated, at least not immediately future events tend to trigger an update somehow. One workaround is to change the underlying data Airplane. Model instead and then call bs. ResetCurrentItem to update the controls. Admittedly, the Model textbox is really not needed because you can edit cells in the Model column directly on the DataGridView.
But, this example shows that the two controls are automatically synchronized:. How do the two controls communicate? What's going on behind the scenes? BindingSource is the ringleader, actually. You can learn a little bit about it by reading the documentation, which says that BindingSource "simplifies binding controls on a form to data by providing currency management, change notification, and other services between Windows Forms controls and data sources".
Currency management? Rather, it's Microsoft's way of saying "currentness". In other words, BindingSource keeps track of which object is the current one in its List. Internally, BindingSource uses a CurrencyManager , which holds a reference to the list and keeps track of the current item. When the user edits the model name, the control modifies the BindingSource. But, how does the control notify the BindingSource about the change to its Text property?
Remember, from a control's perspective, the DataSource is just an Object. Also, I wonder: do controls have some kind of special support for BindingSource specifically, or would they accept other classes as long as they implement a certain interface?
In other words, is data binding based on duck typing , or is it special-cased for certain classes or interfaces? And, what is expected from data sources, in general?
Well, by using Visual Studio and following these instructions , you can trace through the. NET Framework source code.
And, there is a special tool with which you can do the same thing in other versions of Visual Studio, plus, it downloads the complete source code rather than only the part you need. It is also possible to examine the code by disassembling it with Reflector and the FileDisassembler add-in, but this approach does not let you trace through the code. Unfortunately, it's a really enormous and complicated code. After several hours, I figured out how exactly a control notifies the BindingSource that its Text property changed, and how the DataGrid is notified.
I will now explain how, but the explanation is so convoluted you probably won't want to hear it. Feel free to skip a few paragraphs. This is complicated.
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