how to make ADO.Net connection using web.config file

<?xml version=”1.0″?>
<configuration>
 <configSections>
  <sectionGroup name=”system.web.extensions” type=”System.Web.Configuration.SystemWebExtensionsSectionGroup, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″>
   <sectionGroup name=”scripting” type=”System.Web.Configuration.ScriptingSectionGroup, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″>
    <section name=”scriptResourceHandler” type=”System.Web.Configuration.ScriptingScriptResourceHandlerSection, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″ requirePermission=”false” allowDefinition=”MachineToApplication”/>
    <sectionGroup name=”webServices” type=”System.Web.Configuration.ScriptingWebServicesSectionGroup, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″>
     <section name=”jsonSerialization” type=”System.Web.Configuration.ScriptingJsonSerializationSection, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″ requirePermission=”false” allowDefinition=”Everywhere”/>
     <section name=”profileService” type=”System.Web.Configuration.ScriptingProfileServiceSection, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″ requirePermission=”false” allowDefinition=”MachineToApplication”/>
     <section name=”authenticationService” type=”System.Web.Configuration.ScriptingAuthenticationServiceSection, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″ requirePermission=”false” allowDefinition=”MachineToApplication”/>
    </sectionGroup>
   </sectionGroup>
  </sectionGroup>
 </configSections>
 <connectionStrings>
  </connectionStrings>
 <appSettings>
  <add key=”ConStr” value=”Server=localhost;database=master_db;uid=sa;pwd=sa”/>
  <add key=”URLPrefix” value=”http://bhukkad.com”/>
  <!–<add key=”ConStr” value=”Server=.;database=hotel;uid=sa;pwd=sa”/>–>
 </appSettings>
 <system.web>
  <pages>
   <controls>
    <add tagPrefix=”asp” namespace=”System.Web.UI” assembly=”System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″/>
   </controls>
  </pages>
  <!–
          Set compilation debug=”true” to insert debugging
          symbols into the compiled page. Because this
          affects performance, set this value to true only
          during development.
    –>
  <compilation debug=”true”>
   <assemblies>
    <add assembly=”System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″/>
    <add assembly=”System.Design, Version=2.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A”/>
    <add assembly=”System.Web.Extensions.Design, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31BF3856AD364E35″/>
    <add assembly=”System.Windows.Forms, Version=2.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089″/>
    <add assembly=”System.Web, Version=2.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A”/>
    <add assembly=”System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089″/>
    <add assembly=”System.Xml, Version=2.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089″/>
    <add assembly=”System.Drawing, Version=2.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A”/>
    <add assembly=”System.Data, Version=2.0.0.0, Culture=neutral, PublicKeyToken=B77A5C561934E089″/>
    <add assembly=”System.Web.Services, Version=2.0.0.0, Culture=neutral, PublicKeyToken=B03F5F7F11D50A3A”/></assemblies>
  </compilation>
  <httpHandlers>
   <remove verb=”*” path=”*.asmx”/>
   <add verb=”*” path=”*.asmx” validate=”false” type=”System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″/>
   <add verb=”*” path=”*_AppService.axd” validate=”false” type=”System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″/>
   <add verb=”GET,HEAD” path=”ScriptResource.axd” type=”System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″ validate=”false”/>
  </httpHandlers>
  <httpModules>
   <add name=”ScriptModule” type=”System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″/>
  </httpModules>
  <customErrors mode=”Off”/>
 </system.web>
 <system.webServer>
  <validation validateIntegratedModeConfiguration=”false”/>
  <modules>
   <add name=”ScriptModule” preCondition=”integratedMode” type=”System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″/>
  </modules>
  <handlers>
   <remove name=”WebServiceHandlerFactory-Integrated”/>
   <add name=”ScriptHandlerFactory” verb=”*” path=”*.asmx” preCondition=”integratedMode” type=”System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″/>
   <add name=”ScriptHandlerFactoryAppServices” verb=”*” path=”*_AppService.axd” preCondition=”integratedMode” type=”System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″/>
   <add name=”ScriptResource” preCondition=”integratedMode” verb=”GET,HEAD” path=”ScriptResource.axd” type=”System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35″/>
  </handlers>
 </system.webServer>
</configuration>