ADO.NET Entity Framework 試水——並發[3]

  
　　當前數據庫情況如圖所示 

　　 第一步在概念模型設計器裡按照圖所示分別把NotebookBrand和NotebookType屬性的Concurrency Mode設置為Fixed 
  
　　然後我們寫一段代碼來模擬一個並發沖突的情況 

　　Create object context 
  
　　Dim objContext As New NbWhEntities()
  
  Dim objContext As New NbWhEntities() 
   
   Query the same record as entities
  
  Dim laptop = (From aLaptop In objContextNotebook _
  
   Where aLaptopId = _
  
   Select aLaptop)FirstOrDefault() 
   
   Dim laptop = (From aLaptop In objContextNotebook _
  
   Where aLaptopId = _
  
   Select aLaptop)FirstOrDefault() 
   
Modify the entity

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From:http://tw.wingwit.com/Article/program/net/201311/14743.html