Linq模型ObjectContext下查看Sql语句。

ObjectContext 并没有提供 LINQ to SQL DataContext.Log 这样的功能，要查看实际生成的 T-SQL 语句，要么借助 SQL Server Sql Profiler 这样的工具，要么使用 ObjectQuery.ToTraceString() 方法。

using (var context = new TestEntities())

{
    var users1 = context.User.Where(u => u.Name == "user1");
    Console.WriteLine((users1 as ObjectQuery).ToTraceString());
    var users2 = from u in context.User where u.Name == "user1" select u;
    Console.WriteLine((users2 as ObjectQuery).ToTraceString());

    var sql = "SELECT VALUE u FROM TestEntities.User AS u WHERE u.Name = 'user1'";
    var users3 = context.CreateQuery<User>(sql);
    Console.WriteLine(users3.ToTraceString())
}

输出:

SELECT
[Extent1].[Id] AS [Id],
[Extent1].[Name] AS [Name],
[Extent1].[Age] AS [Age]
FROM [dbo].[User] AS [Extent1]
WHERE N'user1' = [Extent1].[Name]
SELECT
[Extent1].[Id] AS [Id],
[Extent1].[Name] AS [Name],
[Extent1].[Age] AS [Age]
FROM [dbo].[User] AS [Extent1]
WHERE N'user1' = [Extent1].[Name]
SELECT
[Extent1].[Id] AS [Id],
[Extent1].[Name] AS [Name],
[Extent1].[Age] AS [Age]
FROM [dbo].[User] AS [Extent1]
WHERE [Extent1].[Name] = 'user1'