Windows forms ado.net entity framework

Writing a File to the Database. Writing a Custom Authentication Plugin. Fractional Seconds. Problems when Using Invalid Dates. Restricting Invalid Dates. Handling Invalid Dates. Building Custom Listeners. Creating a Data Source. Creating the Report. Displaying the Report. Asynchronous Methods. Binary and Nonbinary Issues. The MySqlConnection Object. The MySqlCommand Object. Working with Decoupled Data. Working with Parameters.

Working with Stored Procedures. NET Profile Provider. Tutorial: Web Parts Personalization Provider. Tutorial: Simple Membership Web Provider. Tutorial: Using MySqlScript. Entity Framework 6 Support. Entity Framework Core Support. You can mark the order as canceled X if you select the Cancel Order button, or you can mark the order as filled F if you select the Fill Order button. If you select the Find Order button again, the updated row appears. Create empty Click event handlers for the four buttons on the FillOrCancel form by double-clicking the buttons.

Bring the following two namespaces into scope so that you don't have to fully qualify the names of their members. Run the application and try creating a few customers and orders to verify that everything is working as expected. To verify that the database is updated with your changes, open the Tables node in Server Explorer , right-click on the Customers and Orders nodes, and choose Show Table Data. Skip to main content.

This browser is no longer supported. Download Microsoft Edge More info. Contents Exit focus mode. Create a simple data application by using ADO. Is this page helpful? Please rate your experience Yes No. Any additional feedback? Important To keep the code simple, it doesn't include production-ready exception handling. Note The group box and the label controls add clarity but aren't used in the code. Note In a real application, you should store the connection string securely, as described in Connection strings and configuration files.

These changes can be implemented in the Main method. In the above code below line lanches the forms app with EmployeeContext resolved from IoC service container. Run new Form1 employeeContext ;. EmployeeContext is generated using EntityFrameworkCore scaffolding tool which is discussed below. Context class can be created for single or multiple tables as needed. Please read the article on Understanding Scaffold Commands in Entity framework for more details. We shall be consuming EmployeeContext within Form class but if you need EmployeeContext in other classes or module then you can easily do so, using Constructor injection in any class of your choice.

EmployeeContext can be initialized within the Master Form class using Constructor injections. Find the ProductModel. These are located at approximately lines and This occurrence is located at approximately line Do not replace the second occurrence of HashSet found later in the code.

Save the ProductModel. This should cause the code for entities to be regenerated. If the code does not regenerate automatically, then right click on ProductModel. If you now open the Category. The Products property on the Category class and Category property on the Product class are navigation properties. In Entity Framework, navigation properties provide a way to navigate a relationship between two entity types.

EF gives you an option of loading related entities from the database automatically the first time you access the navigation property. With this type of loading called lazy loading , be aware that the first time you access each navigation property a separate query will be executed against the database if the contents are not already in the context.

When using POCO entity types, EF achieves lazy loading by creating instances of derived proxy types during runtime and then overriding virtual properties in your classes to add the loading hook. To get lazy loading of related objects, you must declare navigation property getters as public and virtual Overridable in Visual Basic , and you class must not be sealed NotOverridable in Visual Basic. When using Database First navigation properties are automatically made virtual to enable lazy loading.

In the Code First section we chose to make the navigation properties virtual for the same reason. Click Finish. Press the pin icon, so the Data Sources window does not auto hide. You may need to hit the refresh button if the window was already visible. In Solution Explorer, double-click the Form1. Select the Category data source and drag it on the form. These controls are bound to the BindingSource categoryBindingSource and Binding Navigator categoryBindingNavigator components that are created as well.

Edit the columns on the categoryDataGridView.