数据库连接的方法

    <connectionStrings>
      <!--<add name="ProwebEntities" connectionString ="Data Source=.;Integrated Security=false;Initial Catalog=Saienyitai;User ID=sa;Password=sa;MultipleActiveResultSets=true" providerName ="System.Data.SqlClient"/>-->

      <!--<add name="ProwebEntities" connectionString ="Data Source=.;Integrated Security=true;Initial Catalog=Saienyitai;MultipleActiveResultSets=true" providerName ="System.Data.SqlClient"/>-->

      <!--<add name="ProwebEntities" connectionString ="Data Source=.;Integrated Security=false;Initial Catalog=Saienyitai;User ID=sa;Password=sa;MultipleActiveResultSets=true" providerName ="System.Data.SqlClient"/>-->

 <!--<add name="ProwebEntities" connectionString ="Data Source=.;Integrated Security=true;Initial Catalog=Saienyitai;MultipleActiveResultSets=true" providerName ="System.Data.SqlClient"/>-->

      <add name="ProwebEntities" connectionString="Data Source=|DataDirectory|Saienyitai.sdf" providerName="System.Data.SqlServerCe.4.0"/>

      <!--<add name="ProwebEntities" connectionString="Data Source=.;Integrated Security=false;Initial Catalog=Saienyitai;User ID=sa;Password=sa;MultipleActiveResultSets=true" providerName="System.Data.SqlClient"/>-->

  <!--<add name="ProwebEntities" connectionString="Data Source=.;Integrated Security=true;Initial Catalog=Saienyitai;MultipleActiveResultSets=true" providerName="System.Data.SqlClient"/>-->
    </connectionStrings>

ProwebEntities为上下文类   Saienyitai为数据库名称  User ID为数据库名称;Password为数据库密码; 做项目时做相应的替换！

MultipleActiveResultSets可以使数据库连接复用。这样就不怕数据库的连接资源被耗尽了。