LINQ到实体如何更新记录 [英] LINQ to Entities how to update a record

问题描述

好了，所以我是新来的都EF和LINQ。我已经想通了如何插入和删除，但由于某些原因的UPDATE似乎逃避我的掌握

Okay, so I'm new to both EF and LINQ. I have figured out how to INSERT and DELETE but for some reason UPDATE seems to escape my grasp.

下面是我的代码示例：

EntityDB dataBase = new EntityDB();
Customer c = new Customer
{
     Name = "Test",
     Gender = "Male
};
dataBase.Customers.AddObject(c);
dataBase.SaveChanges();

上面创建并添加一条记录就好了。

The above creates and adds a record just fine.

Customer c = (from x in dataBase.Customers
             where x.Name == "Test"
             selext x).First();
dataBase.Customers.DeleteObject(c);
dataBase.SaveChanges();

以上有效地删除指定的记录。

The above effectively deletes the specified record.

现在我该如何更新？我似乎无法找到一个 UpdateObject（）对实体采集方法。

Now how do I update? I can't seem to find an "UpdateObject()" method on the entity collection.

推荐答案

只需修改一个返回的实体：

Just modify one of the returned entities:

Customer c = (from x in dataBase.Customers
             where x.Name == "Test"
             select x).First();
c.Name = "New Name";
dataBase.SaveChanges();

请注意，您只能更新一个实体（东西延伸EntityObject，不是你已经使用类似选择新CustomObject {名= x.Name}

Note, you can only update an entity (something that extends EntityObject, not something that you have projected using something like select new CustomObject{Name = x.Name}

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