我正在制作ASP .NET MVC应用程序，在运行项目时出现此错误

Question

I am getting the following error

This is my connection string in web.config

<!--EmployeeContext connection string-->
  <connectionStrings>
    <add name="EmployeeContext" connectionString="Data Source=(LocalDB)\MSSQLLocalDB;AttachDbFilename=D:\VisualStudioProjects\C# projects\LocalDBApplication\LocalDBApplication\Database1.mdf;Integrated Security=True"
   providerName="System.Data.SqlClient" />
  </connectionStrings>

Answer 1

该错误消息很明显，说明您的配置文件中有重复的connectionStrings部分。

Answer 2

Error clearly says you have more than one <conncetionStrings> section specified. Check your code and remove duplicates

Answer 3

It only allowed one <connectionStrings> section in config file. Check your web.config to remove or merge your defined connections.