visual studio 2010 数据库连接配置,该怎么处理

visual studio 2010 数据库连接配置
<connectionStrings>
  当中怎么填? 
  </connectionStrings>

App_Data中有db_ExamOnline.mdf

------解决方案--------------------------------------------------------
<add key="access_con" value="Provider=Microsoft.Jet.OleDb.4.0;Data Source=|DataDirectory|\\db_ExamOnline.mdb" ></add>
------解决方案--------------------------------------------------------

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<add key="access_con" value="Provider=Microsoft.Jet.OleDb.4.0;Data Source=|DataDirectory|\\db_ExamOnline.mdb" ></add>