EF连接字符串为DbContext构造函数 [英] EF connection string as DbContext constructor argument

问题描述

我已经看到一些代码示例，当创建新的DbContext时，将实体框架连接字符串作为构造函数参数。但是当我将一个新的ADO.NET实体数据模型添加到一个项目（数据库中）时，DbContext只有一个无参数的构造函数。

I have seen some code sample that put an entity framework connection string as a constructor argument when creating a new DbContext. But when I added a new ADO.NET entity data model into a project (database first), the DbContext only has one parameterless constructor.

我错过了一步吗？我应该怎么做才能获得该构造函数？

Did I miss a step? What should I do to get that constructor?

Visual Studio 2012定位.net框架4.5实体框架5。

Visual Studio 2012 targeting .net framework 4.5 entity framework 5.

推荐答案

根据Arthur Vickers的建议，我将部分类扩展为接受连接字符串的构造函数。在C＃（非常类似于hege的答案）：

As per Arthur Vickers' suggestion, I am extending the partial class to have a constructor that accepts connection string. In C# (very similar to hege's answer):

public partial class MyEFEntities
{
    public MyEFEntities(string connectionstring)
        : base(connectionstring)
    {
    }
}

或在VB.Net中：

Partial Public Class MyEFEntities
    Public Sub New(ConnectionString As String)
        MyBase.New(ConnectionString)
    End Sub
End Class

这篇关于EF连接字符串为DbContext构造函数的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！