使用MVC5的Entity Framework 教程源码
创建了一个使用实体框架和SQL Server Express LocalDB来存储和显示数据的简单Web应用程序. 实现了基本的CRUD和排序、筛选、分页及分组功能. using System; using System.Collections.Generic; using System.Data; using System.Data.Entity; using System.Linq; using System.Net; using System.Web; using System.Web.Mvc; using ContosoUniversity.DAL; using ContosoUniversity.Models; using PagedList; namespace ContosoUniversity.Controllers { public class StudentsController : Controller { private SchoolContext db = new SchoolContext(); // GET: Students //public ActionResult Index() //{ // return View(db.Students.ToList()); //} /* step1 public ActionResult Index(string sortOrder) { ViewBag.NameSortParm = String.IsNullOrEmpty(sortOrder) ? "name_desc" : ""; ViewBag.DateSortParm = sortOrder == "Date" ? "date_desc" : "Date"; var students = from s in db.Students select s; switch (sortOrder) { case "name_desc": students = students.OrderByDescending(s => s.LastName); break; case "Date": students = students.OrderBy(s => s.EnrollmentDate); break; case "date_desc": students = students.OrderByDescending(s => s.EnrollmentDate); break; default: students = students.OrderBy(s => s.LastName); break; } return View(students.ToList()); } */ /*step2 public ViewResult Index(string sortOrder, string searchString) { ViewBag.NameSortParm = String.IsNullOrEmpty(sortOrder) ? "name_desc" : ""; ViewBag.DateSortParm = sortOrder == "Date" ? "date_desc" : "Date"; var students = from s in db.Students select s; if (!String.IsNullOrEmpty(searchString)) { students = students.Where(s => s.LastName.Contains(searchString) || s.FirstMidName.Contains(searchString)); } switch (sortOrder) { case "name_desc": students = students.OrderByDescending(s => s.LastName); break; case "Date": students = students.OrderBy(s => s.EnrollmentDate); break; case "date_desc": students = students.OrderByDescending(s => s.EnrollmentDate); break; default: students = students.OrderBy(s => s.LastName); break; } return View(students.ToList()); } */ public ViewResult Index(string sortOrder, string currentFilter, string searchString, int? page) { ViewBag.CurrentSort = sortOrder; ViewBag.NameSortParm = String.IsNullOrEmpty(sortOrder) ? "name_desc" : ""; ViewBag.DateSortParm = sortOrder == "Date" ? "date_desc" : "Date"; if (searchString != null) { page = 1; } else { searchString = currentFilter; } ViewBag.CurrentFilter = searchString; var students = from s in db.Students select s; if (!String.IsNullOrEmpty(searchString)) { students = students.Where(s => s.LastName.Contains(searchString) || s.FirstMidName.Contains(searchString)); } switch (sortOrder) { case "name_desc": students = students.OrderByDescending(s => s.LastName); break; case "Date": students = students.OrderBy(s => s.EnrollmentDate); break; case "date_desc": students = students.OrderByDescending(s => s.EnrollmentDate); break; default: // Name ascending students = students.OrderBy(s => s.LastName); break; } int pageSize = 6; int pageNumber = (page ?? 1); return View(students.ToPagedList(pageNumber, pageSize)); } // GET: Students/Details/5 public ActionResult Details(int? id) { if (id == null) { return new HttpStatusCodeResult(HttpStatusCode.BadRequest); } Student student = db.Students.Find(id); if (student == null) { return HttpNotFound(); } return View(student); } // GET: Students/Create public ActionResult Create() { return View(); } // POST: Students/Create // 为了防止“过多发布”攻击，请启用要绑定到的特定属性，有关 // 详细信息，请参阅 http://go.microsoft.com/fwlink/?LinkId=317598。 [HttpPost] [ValidateAntiForgeryToken] public ActionResult Create([Bind(Include = "LastName,FirstMidName,EnrollmentDate")] Student student) { try { if (ModelState.IsValid) { db.Students.Add(student); db.SaveChanges(); return RedirectToAction("Index"); } } catch(DataException /* dex */) { //Log the error (uncomment dex variable name and add a line here to write a log. ModelState.AddModelError("", "Unable to save changes. Try again, and if the problem persists see your system administrator."); } return View(student); } // GET: Students/Edit/5 public ActionResult Edit(int? id) { if (id == null) { return new HttpStatusCodeResult(HttpStatusCode.BadRequest); } Student student = db.Students.Find(id); if (student == null) { return HttpNotFound(); } return View(student); } // POST: Students/Edit/5 // 为了防止“过多发布”攻击，请启用要绑定到的特定属性，有关 // 详细信息，请参阅 http://go.microsoft.com/fwlink/?LinkId=317598。 [HttpPost] [ValidateAntiForgeryToken] public ActionResult Edit([Bind(Include = "ID,LastName,FirstMidName,EnrollmentDate")] Student student) { if (ModelState.IsValid) { db.Entry(student).State = EntityState.Modified; db.SaveChanges(); return RedirectToAction("Index"); } return View(student); } // GET: Students/Delete/5 public ActionResult Delete(int? id) { if (id == null) { return new HttpStatusCodeResult(HttpStatusCode.BadRequest); } //if (saveChangesError.GetValueOrDefault()) { // ViewBag.ErrorMessage = "Delete failed. Try again, and if the problem persists see your system administrator."; //} Student student = db.Students.Find(id); if (student == null) { return HttpNotFound(); } return View(student); } // POST: Students/Delete/5 [HttpPost, ActionName("Delete")] [ValidateAntiForgeryToken] public ActionResult DeleteConfirmed(int id) { Student student = db.Students.Find(id); db.Students.Remove(student); db.SaveChanges(); return RedirectToAction("Index"); } protected override void Dispose(bool disposing) { if (disposing) { db.Dispose(); } base.Dispose(disposing); } } }
