使用Entity Framework模型插入数据

Roc*_*shy 84 .net c# entity-framework

我正在尝试使用Entity Framework模型在我的数据库中插入一些数据,但由于某些未知的原因,它什么也没做.

我在这里错过了什么吗?

using (var context = new DatabaseEntities())
{
    var t = new test
    {
        ID = Guid.NewGuid(),
        name = "blah",
    };
    context.AddTotest(t);
    context.SaveChanges();
}
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Dev*_*per 106

它应该是:

context.TableName.AddObject(TableEntityInstance);
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哪里:

  1. TableName:数据库中表的名称.
  2. TableEntityInstance:表实体类的实例.

如果你的表是Orders,那么:

Order order = new Order();
context.Orders.AddObject(order);
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例如:

 var id = Guid.NewGuid();

 // insert
 using (var db = new EfContext("name=EfSample"))
 {
    var customers = db.Set<Customer>();
    customers.Add( new Customer { CustomerId = id, Name = "John Doe" } );

    db.SaveChanges();
 }
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这是一个实例:

public void UpdatePlayerScreen(byte[] imageBytes, string installationKey)
{
  var player = (from p in this.ObjectContext.Players where p.InstallationKey == installationKey select p).FirstOrDefault();

  var current = (from d in this.ObjectContext.Screenshots where d.PlayerID == player.ID select d).FirstOrDefault();

  if (current != null)
  {
    current.Screen = imageBytes;
    current.Refreshed = DateTime.Now;

    this.ObjectContext.SaveChanges();
  }
  else
  {
    Screenshot screenshot = new Screenshot();

    screenshot.ID = Guid.NewGuid();
    screenshot.Interval = 1000;
    screenshot.IsTurnedOn = true;
    screenshot.PlayerID = player.ID;
    screenshot.Refreshed = DateTime.Now;
    screenshot.Screen = imageBytes;

    this.ObjectContext.Screenshots.AddObject(screenshot);
    this.ObjectContext.SaveChanges();
  }
}
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  • 使用.Add而不是.AddObject (25认同)
  • 在EF 6上,您将使用.Add而不是.AddObject (9认同)

Naw*_*ada 38

var context = new DatabaseEntities();

var t = new test //Make sure you have a table called test in DB
{
    ID = Guid.NewGuid(),
    name = "blah",
};

context.test.Add(t);
context.SaveChanges();
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应该这样做


小智 7

[HttpPost] //在按钮点击事件上编写逻辑时使用它

public ActionResult DemoInsert(EmployeeModel emp)
{
    Employee emptbl = new Employee();    // make object of table
    emptbl.EmpName = emp.EmpName;
    emptbl.EmpAddress = emp.EmpAddress;  // add if any field you want insert
    dbc.Employees.Add(emptbl);           // pass the table object 
    dbc.SaveChanges();

    return View();
}
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