从web.config读取连接字符串

Question

如何从web.config文件中读取连接字符串到类库中包含的公共类？

我试过了:

WebConfigurationManager

ConfigurationManager

但是这些类在我的类库中无法识别.

Answer 1

您需要添加引用System.Configuration然后使用:

System.Configuration.ConfigurationManager.
    ConnectionStrings["connectionStringName"].ConnectionString;

Answer 2

添加System.Configuration作为参考.

出于某些奇怪的原因,默认情况下不包含它.

Answer 3

C#

// Add a using directive at the top of your code file    
using System.Configuration;

// Within the code body set your variable    
string cs = ConfigurationManager.ConnectionStrings["connectionStringName"].ConnectionString;

VB

' Add an Imports statement at the top of your code file    
Imports System.Configuration

' Within the code body set your variable    
Dim cs as String = ConfigurationManager.ConnectionStrings("connectionStringName").ConnectionString

Answer 4

添加System.Configuration作为参考然后:

 using System.Configuration;

 ...

 string conn = 
    ConfigurationManager.ConnectionStrings["ConnectionName"].ConnectionString;

Answer 5

我想你需要添加一个对System.Configuration程序集的引用,如果还没有添加.

此外,您可能需要在代码文件的顶部插入以下行:

using System.Configuration;

Answer 6

在VB:这应该工作

ConfigurationManager.ConnectionStrings("SQLServer").ConnectionString

在C#它(将根据Ala的评论)

ConfigurationManager.ConnectionStrings["SQLServer"].ConnectionString

Answer 7

您必须在页面或类的顶部调用此类:

using System.Configuration;

然后,您可以使用此方法返回连接字符串以准备传递给sqlconnection对象以继续您的工作,如下所示:

    private string ReturnConnectionString()
    {
       // Put the name the Sqlconnection from WebConfig..
        return ConfigurationManager.ConnectionStrings["DBWebConfigString"].ConnectionString;
    }

只是为了明确说明这是Web配置中的价值:

  <add name="DBWebConfigString" connectionString="....." />   </connectionStrings>

Answer 8

using System.Configuration;


string conn = ConfigurationManager.ConnectionStrings["ConStringName"].ToString();

Answer 9

using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data.SqlClient;
using System.Drawing;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.DataVisualization.Charting;
using System.Web.UI.WebControls;  

C#

string constring = ConfigurationManager.ConnectionStrings["ABCD"].ConnectionString;
                using (SqlConnection con = new SqlConnection(constring))

以下网页>配置文件代码

<connectionStrings>
    <add name="ABCD" connectionString="Data Source=DESKTOP-SU3NKUU\MSSQLSERVER2016;Initial Catalog=TESTKISWRMIP;Integrated Security=True" providerName="System.Data.SqlClient"/>
  </connectionStrings>

在ablove Code ABCD中是连接名称