Here are the steps to seed the NorthwindCafe database:
1. Create a file call DBInitializer in the NorthwindCafe.Web "Models" folder, in the file type in the following code
using System.Linq; namespace NorthwindCafe.Web.Models { public class DbInitializer { public static void Initialize(NorthwindContext context) { context.Database.EnsureCreated(); if(context.Categories.Any()) { return; } var categories = new Category[] { new Category {Name = "Coffee", Description="Coffee", Products = new Product[] { new Product { Name = "Dark Roast", Description = "Dark Roast", Price = 2.0M } } }, new Category {Name = "Tea", Description="Tea", Products = new Product[] { new Product { Name = "Chai", Description = "Chai", Price = 1.5M } } }, new Category {Name = "Pastry", Description="Pastry", Products = new Product[] { new Product { Name = "Cupcake", Description = "Cupcake", Price = 1.25M } } }, new Category {Name = "Food", Description = "Food", Products = new Product[] { new Product { Name = "Hamburger", Description = "Hamburger", Price = 5.0M } } } }; foreach (var c in categories) { context.Categories.Add(c); } context.SaveChanges(); } } }
The code is pretty straight forward it checks for categories in the database with the line
context.Categories.Any()
if there are Categories in the database then it just get out of the method else it populates the database with the categories object
2. Now open the Startup.cs file and add the NorthwindContext to the Configure method
public void Configure(IApplicationBuilder app, IHostingEnvironment env, NorthwindContext context) { app.UseStaticFiles(); app.UseMvc(config => { config.MapRoute( name: "Default", template: "{controller}/{action}/{id?}", defaults: new { controller = "Home", action = "Index" } ); }); DbInitializer.Initialize(context); }
Add the line DbIntitializer.Initialize(context) to the end of the method to seed the database on startup Run by pressing CTRL+F5 the application and the Categories table will be populated with seed data
The Products table will be populated as well notice how the CategoryId has been assigned to the appropriate category
Mua vé máy bay tại Aivivu, tham khảo
ReplyDeletesăn vé máy bay giá rẻ đi Mỹ
khi nào có vé máy bay từ mỹ về việt nam
vé máy bay từ Toronto về việt nam
vé từ nhật về việt nam
ve may bay vietnam airline tu han quoc ve viet nam
Vé máy bay từ Đài Loan về Việt Nam
chi phí vé máy bay cho chuyên gia nước ngoài