从web.config读取连接字符串

System.Configuration

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

// 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;

\' 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

 using System.Configuration;

 ...

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

using System.Configuration;

VB

ConfigurationManager.ConnectionStrings(\"SQLServer\").ConnectionString

C#

ConfigurationManager.ConnectionStrings[\"SQLServer\"].ConnectionString

using System.Configuration;

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

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

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;  

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

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

using System.Configuration;


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

using System.Configuration;


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

using System.Configuration;

using System.Configuration;