我想创建一个简单的数据库Code First Approcah EF 5.0。实体框架代码优先的方法获取错误:“底层提供商在打开失败”
我有Employee类:
public class Employee
{
public int EmployeeID { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
}
我有EmployeeDbContext类:
public class EmployeeDbContext : DbContext
{
static EmployeeDbContext()
{
Database.SetInitializer<EmployeeDbContext>(null);
}
public DbSet<Employee> Employees { get; set; }
}
和存储库类:
public class Repository
{
public List<Employee> GetEmployees()
{
EmployeeDbContext MyDataBase = new EmployeeDbContext();
return MyDataBase.Employees.ToList();
}
}
我已经创建WebFrom文件,其内部一个GridView并将其与ObjectDataSource连接到存储库(屏幕截图):http://s3.postimg.org/jqvm89scz/Capture.png
这是我的ConnectionString:
<add name="EmployeeDbContext" connectionString="server=.; Database=Sample;Trusted_Connection=True; Persist Security Info=True;" providerName="System.Data.SqlClient" />
当我调试这个IM在得到这个错误 “回归MyDataBase.Employees.ToList();”
An exception of type 'System.Data.Entity.Core.EntityException' occurred in
EntityFramework.SqlServer.dll but was not handled in user code
Additional information: The underlying provider failed on Open.
我已经试过这条线这MyDataBase.Database.Connection.Open();
之前添加和得到这个错误:
Cannot open database "Sample" requested by the login. The login failed.
UPDATE
当我改变在ConnectionString数据库到exisiting一个( Northwind数据库)的工作,我只是再次提到,即时通讯尝试创建一个不存在的数据库。
您是否尝试使用您的connectionString连接到数据库?新的SqlConnection(@“数据源=。\ SQLEXPRESS; AttachDbFilename = | DataDirectory | \ MyDb2.mdf;集成安全性= True;用户实例= True”) – yonexbat
抱歉不明白,我该怎么办? – Yaniv
好吧,那个更新使所有的差异,从来没有测试 –