ConfigurationManager throwing null exception when trying to read connection string in .NET 4.0-CodePudding

I am working on .NET Framework 4.0 Class Library project along with ADO.NET. I have connectionString inside the App.config which I am trying to read using ConfigurationManager but getting null reference exception.

Error

app.config

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
  </configSections>
 <connectionStrings>
    <add name ="dbConnection" connectionString="Data Source=xyz;Integrated Security=True" providerName="System.Data.SqlClient" />
</connectionStrings>
</configuration>

Reading ConnectionString

using System.Configuration;

var x22 = ConfigurationManager.ConnectionStrings["dbConnection"].ConnectionString;

CodePudding user response：

In your solution explorer and under reference node, check if assembly System.Configuration has been added and there is not any error regarding to your references.

But, your code is correct and I suggest to you try to avoid this error by checking null situation in return value of that command.

CodePudding user response：

in app config

<connectionStrings>
    <add name="[name]" connectionString="[YOUR CONNECTION]" />
</connectionStrings>

call your connectionString

 ConfigurationManager.ConnectionStrings["name"].ConnectionString