• ASP.NET MVC5--Contains


    前言:

    * The Contains  method is run on the database, not the c# code above. On the database, Contains maps to SQL LIKE,  which is case insensitive.

    这句话的意思是Contains()方法,运行在数据库中,而不是C#代码上,在数据库中,Contains就像SQL中的LIKE关键字,它是大小写敏感的。

    一:我们来为Index页面添加一个模糊查询,在控制器中找到Index方法,修改如下:

     1   public ActionResult Index(string searchString)
     2         {
     3            
     4             var movies = from m in db.Movies select m;
     5 
     6             if (!string.IsNullOrEmpty(searchString))
     7             {
     8                 movies = movies.Where(s => s.Title.Contains(searchString));
     9             }
    10             return View(movies);
    11         }

    执行完

     var movies = from m in db.Movies select m;

    这句代码之后,我们侦听到movies执行的SQL语句为:
    1 SELECT   
    2 [Extent1].[ID] AS [ID],   
    3 [Extent1].[Title] AS [Title],  
    4 [Extent1].[ReleaseDate] AS [ReleaseDate],  
    5 [Extent1].[Genre] AS [Genre],    
    6 [Extent1].[Price] AS [Price]  
    7 FROM [dbo].[Movies] AS [Extent1]

    执行完这句之后 movies的SQL语句为:

    1 SELECT  
    2 [Extent1].[ID] AS [ID],    
    3 [Extent1].[Title] AS [Title],  
    4 [Extent1].[ReleaseDate] AS [ReleaseDate],   
    5 [Extent1].[Genre] AS [Genre],   
    6 [Extent1].[Price] AS [Price]  
    7 FROM [dbo].[Movies] AS [Extent1]  
    8 WHERE [Extent1].[Title] LIKE @p__linq__0 ESCAPE N'~'

    可以看得出来,Contains方法,生成了Like后面的语句。

     
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  • 原文地址:https://www.cnblogs.com/caofangsheng/p/4590974.html
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