具有Microsoft SQL Server数据库的C＃Winform应用程序

Question

I developed a small application in C# in which I use a SQL Server database, but when I run my application I get this error:

An unhandled exception of type 'System.Configuration.ConfigurationErrorsException' occurred in System.Configuration.dll

Additional information: Configuration system failed to initialize

Can anyone help me fix this error?

The code of my save button shown in this image where exception error occurred and My app.config. file is:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <startup> 
        <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
    </startup>
  <connectionstring>
    <add name="dbx" connectionstring="Data Source=JAWADKHAN-PC;Initial Catalog=jawad;Integrated Security=True" Providername="System.Data.SQLClient">
    </add>
      </connectionstring>
</configuration>

Answer 1

Check your app.config file. Add configSections after configuration section. change sequence like :

 <configuration>
     <configSections>
      ....
     </configsections>
     .
     .

if this does not solve your problem then post app.config file to review.