Fetching connection string from appconfig file in c#

Question

I have the following connection string declared in my app.config file:

Answer 1

First, you must add the appSettings tag

 <connectionStrings>
    <appSettings>
      <add name="SqlConnectionString" connectionString="Data Source=xxx.xx.xx.xx;Initial Catalog=xxxxx;User Id=xx;Password=xxx;" providerName="System.Data.SqlClient" />
    </appSettings>
  </connectionStrings>

Second, add a reference to System.Configuration to your project and insert a using System.Configuration in the source.

Then, you can use ConfigurationManager.AppSettings to access your config setting:

string result = ConfigurationSettings.AppSettings["SqlConnectionString"];

Answer 2

One thing I've noticed when compiling WinForm App in VS 2013:

I add connection strings my Settings File - which updates my app.config file

When I would expect:

var connectionString = ConfigurationManager.ConnectionStrings["theConnectionStringName"].ConnectionString;

I have to write:

var connectionString = ConfigurationManager.ConnectionStrings["MyAppNameSpace.Properties.Settings.theConnectionStringName"].ConnectionString;

Everything else is business as usual

Answer 3

Same problem. Based on Merlyn Morgan-Graham and Edward Zhu comments, I rebuilt my project, which used the app.config to create a myapp.exe.config file with the connection string. Original first syntax then worked.

Other problem: Tried using the project properties dialog to modify the connection string and it added "project.My.Mysettings. to the connection string name. Which caused failure.

Answer 4

<configuration>
  <appSettings>
   <add key="ConnectionString" value="blah blah blah"/>  </appSettings>
  </configuration>

Will the above configuration works with the API/code like:

string str = ConfigurationSettings.AppSettings["SqlConnectionString"];