c# - DataGrid - 防止并发访问行

Question

我需要编写一个简单的数据网格表单，允许用户编辑单元格 - 问题是不同的人可以同时编辑它，因此并发性成为一个问题

我正在使用数据库支持的数据

我似乎有两个选择:

1) 在允许编辑之前不断轮询数据库并刷新数据网格中的数据 - 这意味着需要在编辑后立即更新数据库，而不是允许编辑、然后让用户查看然后提交的首选方式。

2) 允许脏编辑，然后阻止用户向数据库提交他们想要的更改

任何人都可以描述一种允许用户同时编辑行的机制，这将使实现变得容易吗？

编辑:我的问题是如何在 C# 中实现这一点 - 我已经添加了锁定列，但这仍然不够 - 如果 usera 尝试编辑 row1 并提交更改 userB 尝试编辑 row1 的过时版本，这将不会被捕获这是一个大问题

Answer 1

您有以下选项，但不限于:

Optimistic Concurrency - assume that while there may be concurrency conflicts every now and then, the vast majority of the time such conflicts won't arise; therefore, if a conflict does arise, simply inform the user that their changes can't be saved because another user has modified the same data

Pessimistic Concurrency - assume that concurrency conflicts are commonplace and that users won't tolerate being told their changes weren't saved due to another user's concurrent activity; therefore, when one user starts updating a record, lock it, thereby preventing any other users from editing or deleting that record until the user commits their modifications

有关引用和详细信息，请参阅:

• Implementing Optimistic Concurrency

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乐观并发

PeopleDataContext people = new PeopleDataContext();     
Person p = people.People.Single(person => person.ID == 1);     
p.IDRole = 2;

try
{ people.SubmitChanges(ConflictMode.ContinueOnConflict); }

catch (ChangeConflictException cce)
{ people.ChangeConflicts.ResolveAll(RefreshMode.KeepChanges); }

悲观并发

PeopleDataContext people = new PeopleDataContext();

using (TransactionScope t = new TransactionScope())
{
   Person p = people.People.Single(person => person.ID == 1);

   p.LastName = "Pessimistic";
   p.FirstName = "Concurrency";    

   people.SubmitChanges();     
   t.Complete();
}

引用:

• LINQ to ADO.NET—Optimistic Concurrency Database Transactions

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