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  • DataContext.ExecuteQuery的两种方法调用

    ExecuteQuery主要用于DataContext类直接执行SQL语句的查询,在MSDN上有两种执行方法,下面为两种方法的不同调用:

    1、ExecuteQuery<TResult>(String, Object[])   应该是微软的推荐方法,网上几乎都在用的方法

    NorthwindDataContext ctx = new NorthwindDataContext("server=xxx;database=Northwind;uid=xxx;pwd=xxx");
    
    string newcity = "Shanghai";
    
    ctx.ExecuteCommand("update Customers set City={0} where CustomerID like 'A%'", newcity);
    
    IEnumerable<Customer> customers = ctx.ExecuteQuery<Customer>("select * from Customers where CustomerID like 'A%'");
    
    GridView1.DataSource = customers;
    
    GridView1.DataBind();

    2、ExecuteQuery(Type, String, Object[])  Type为要返回的 IEnumerable<T> 的类型。

    DataContext db = new DataContext("Data Source=*******;Initial Catalog=*****;Persist Security Info=True;User ID=sa;Password=*****");
                StreamWriter sw = new StreamWriter(Server.MapPath("log.txt"), true);
                //db.Log = sw;
                Table<NewsList> news = db.GetTable<NewsList>();
                var select = from p in news select new { 标题 = p.title };
                IDbCommand cmd = db.GetCommand(select);
                var newss = db.ExecuteQuery(typeof(NewsList), "SELECT NewsID,TITLE FROM lmh_Newslist");
                foreach (var s in newss)
                {
                    NewsList s1 = (NewsList)s;
                    //Response.Write(s1.title);
                }
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  • 原文地址:https://www.cnblogs.com/superfeeling/p/4384768.html
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