Updating database with dataset
The default is to create an auto-incrementing integer, Run a statement on the database directly.Allows for the execution of arbitrary read/write queries.The final three lines of our Save code are these: btn Cancel. The whole of the code for your Save button should look like this: Try it out.When you start your programme, click the Add New button to clear the textboxes. When you close down your project and open it up again, the new record should still be there.Further positional and keyword arguments will be used for parameter binding.To include a positional argument in your query, use question marks in the query (i.e.
Of course, we have yet to call our new method into action. Add a try catch statement: try catch (Exception err) For the try part, add the following: try As the first line of the try part, we have this: obj Connect.
What we need to do here is to call Navigate Records. After a new record has been entered into the text boxes, we can save it. To save a record, you need to do two things: save it to the Dataset, and save it to the underlying database. Now add the following method: public void Update Database( System. Data Set ds ) So this is a public method that doesn't return a value (void). In between the round brackets of Update Database have a look at what the code is: System. Data Set ds This is a Data Set being passed to the method. Our Data Set, remember, is where all the records are kept, even the ones that have changed. Sql Command Builder( da_1 ); We've called our Command Builder cb. Tables ); The Command Builder has a property called Data Adapter.
When the form loads it will look like this (we've put our buttons on a Group Box): When you click the Add New button, the form will look like this: But all the code does is to clear the four textboxes of text. Return to Design Time and double click your Cancel button. If your Database Connections class is not open, double click it in the Solution Explorer to get at the code.
Update Database(ds); Here, we access our Database Connections object (obj Connect), and call our new method Update Database.
In between the round brackets of our Update Database method we have the name of our Data Set, which is ds.
Notice the next two lines: Max Rows = Max Rows 1; inc = Max Rows - 1; Because we have added a new Row to the Dataset, we also need to add 1 to the Max Rows variable.