private void btnEFUpdatingData_Click(object sender, EventArgs e)
{
using (var ctx = new NorthwindsEntities())
{
Categories cat = ctx.Categories.First(c => c.CategoryName == "Produce");
cat.Description = "Dried fruit and bean curd - modified";
ctx.SaveChanges();
}
// Updating records is just as trivial.The following code sample retrieves the Category with the name
// Alcohol, changes its description, and then updates the record in the database:
//Category category = db.Categories.First(c => c.CategoryName == "Alcohol");
// category.Description = "Happy People";
// db.SaveChanges();
}
private void btnEFDeletingData_Click(object sender, EventArgs e)
{
using (var ctx = new NorthwindsEntities())
{
Categories cat = ctx.Categories.First(c => c.CategoryName == "teste1");
ctx.Categories.Remove(cat);
ctx.SaveChanges();
}
// You can also delete records by using just a few lines of code.
// using (NorthwindsEntities db = new NorthwindsEntities())
// {
// Category category = db.Categories.First(c => c.CategoryName == "Alcohol");
// db.Categories.Remove(category);
// db.SaveChanges();
// }
// In Entity Framework 5.0 you use the Remove method.In previous versions the method was called
// DeleteObject.
}
private void btnEFInsertingData_Click(object sender, EventArgs e)
{
using (var ctx = new NorthwindsEntities())
{
Categories cat = new Categories();
cat.CategoryName = "teste1";
cat.Description = "Test Description";
//
ctx.Categories.Add(cat);
ctx.SaveChanges();
//
// This code created an instance of the Category class and initialized its properties. It then added
// the object to the Categories property of the NorthwindsEntities.The SaveChanges() method
// is then called to add the record to the database. Again, there was no SQL syntax needed; the Entity
// Framework handled all that behind the scenes.
}
}
