用实体框架删除一个项目 [英] Deleting an item with entity framework

问题描述

我正在尝试使用实体框架删除一个对象，并在互联网上的所有教程中发现，为了做到这一点，你必须调用 DeleteObject 方法上下文。我尝试这样做，但似乎我没有 DeleteObject 方法。

这是我的代码：

  public void DeleteBook（int bookId）
 {
 Book book =（Book）bookContext.Books.Where（b = > b.Id == bookId）.First（）; 
 bookContext.DeleteObject（book）; 
} 
  

这是我得到的错误：

$ $$$$$$不含DeleteObject的定义，而没有扩展方法DeleteObject接受DataAccess.Models类型的第一个参数。可以找到BooksEntities（您是否缺少using指令或程序集参考？）

我做错了什么？

解决方案

您是否使用DbContext或ObjectContext？如果您有DbContext，您需要使用删除功能：

  public void DeleteBook（int bookId）
 {
 Book book = （Book）bookContext.Books.Where（b => b.Id == bookId）.First（）; 
 bookContext.Books.Remove（book）; 
} 
  

I am trying to delete an object using Entity Framework and on all the tutorials on the internet I found that in order to do that you have to call the DeleteObject method on the context. I tried doing that but it seems I have no DeleteObject methods.

Here is my code:

public void DeleteBook(int bookId)
    {
        Book book = (Book)bookContext.Books.Where(b => b.Id == bookId).First();
        bookContext.DeleteObject(book);
    }

This is the error I get:

'DataAccess.Models.BooksEntities' does not contain a definition for 'DeleteObject' and no extension method 'DeleteObject' accepting a first argument of type 'DataAccess.Models.BooksEntities' could be found (are you missing a using directive or an assembly reference?)

What am I doing wrong?

解决方案

Are you using a DbContext or an ObjectContext? If you have a DbContext you need to use the Remove function:

public void DeleteBook(int bookId)
    {
        Book book = (Book)bookContext.Books.Where(b => b.Id == bookId).First();
        bookContext.Books.Remove(book);
    }

这篇关于用实体框架删除一个项目的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！