Hello!
I use VS2005 and C#.
I'm looking at ADO.NET and have found some test tutorial on
microsoft MSDN.
It can be found on google when searching for "Walkthroug h: Saving Data to a
Database (Single Table)"
You must have access to the Northwind sample database.
I have followed the walkthrought in this tutorial exectly but it doesn't
save data back to the worthwind database as the tutorial say.
The tutorial say the following.
1. Create a project
2. Create a Data Source by using the Northwind database table customer
3. To set the controls for the items in the Data Sources window.
Expand the Customers node in the Data Sources window.
Change the control for the Customers table to individual controls by
selecting Details from the drop-down list on the Customers node.
4. Create data-bound controls on the form
Drag the main Customers node from the Data Sources window onto
Form1.
5. Modifying the Code to Update the Database
You can update the database by calling the Update method of the
CustomersTableA dapter. By default, an event handler for the
BindingNavigato r's Save button is added to the form's code to send
updates to the database. This procedure modifies the code to include
error
handling by wrapping the update call in a try-catch block.
You can modify the code to suit the needs of your application.
6. To add update logic to the application
Double-click the Save button on the BindingNavigato r to open the
Code Editor to the bindingNavigato rSaveItem_Click event handler.
Replace the code in the event handler to add some error handling.
The code should look like the following:
try
{
this.Validate() ;
this.customersB indingSource.En dEdit();
this.customersT ableAdapter.Upd ate(this.northw indDataSet.Cust omers);
MessageBox.Show ("Update successful");
}
catch (System.Excepti on ex)
{
MessageBox.Show ("Update failed");
}
7. Testing the Application
Press F5.
Note here Update successful is written so everything seems normal.
Make some changes to the data of one or more records.
Press the Save button.(It's a diskett icon)
Check the values in the database to verify that the changes were saved.
So I do the following change some data in one of the control(text field)
and then click the diskett
icon meaning I saving the data back to the database. If I now go to the next
record and then go back to the previous record the change is there. So I
manage to change in the dataset but if I then close the application and look
in the database my changes has not changed anything in the database.I can't
understand why this doesn't work.
Is this a bug perhaps. I would be very glad if someone have any comment
about my problem.
Is it possible to trace in some way why this row
this.customersT ableAdapter.Upd ate(this.northw indDataSet.Cust omers);
doesn't update the customer table in the northwind database.
//Tony
