In this article we are going to explore data operations using ADO.NET Entity Framework over our SQL Azure database. The data model creation which is an essential part required was discussed in the previous article.
Pre-Requisites
For working on this application, you need to have the following pre-requisites.
- Azure project with web role
- Entity data model with Employee class
You may use the project from the previous article.
After having the above, place the following on the Default.aspx page
- 4 buttons with labels Insert, Update, Delete, Refresh
- A grid control
Insert Operation
For creating a new employee, use the following code in the Insert button click event.
mysqlazureEntities context = new mysqlazureEntities();
Employee employe = new Employee();
employe.Name = "New Employee from EF";
context.AddToEmployees(employe);
context.SaveChanges();
Update Operation
For creating a new employee, use the following code in the Update button click event.
mysqlazureEntities context = new mysqlazureEntities();
Employee employee = context.Employees.Where(emp => emp.Name == "New Employee from EF").FirstOrDefault();
if (employee != null)
employee.Name = "Updated Name";
context.SaveChanges();
Delete Operation
For creating a new employee, use the following code in the Delete button click event.
mysqlazureEntities context = new mysqlazureEntities();
Employee employee = context.Employees.Where(emp => (emp.Name == "New Employee from EF" || emp.Name=="Updated Name")).FirstOrDefault();
if (employee != null)
context.DeleteObject(employee);
context.SaveChanges();
Select Operation
For creating a new employee, use the following code in the Refresh button click event.
GridView grid = GridView1;
grid.Columns.Clear();
grid.Columns.Add(new BoundField() { HeaderText = "Id", DataField = "Id" });
grid.Columns.Add(new BoundField() { HeaderText = "Name", DataField = "Name" });
mysqlazureEntities context = new mysqlazureEntities();
grid.DataSource = context.Employees.ToList();
grid.DataBind();
On executing the application and playing with the buttons you can view the following results.
Summary
In this article we have explored the data operations using ADO.NET Entity Framework over our SQL Azure database. You need to change the database name, user name and password in the configuration file.