Exemple #1
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        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();

        }
Exemple #2
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 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.
 }
Exemple #3
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 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.
     }
 }