Code to Get Path from App.config in C#

app.config:
<?xml version="1.0" encoding="utf-8" ?>
<configuration>
   <configSections>
</configSections>
<connectionStrings>
   <add name="ConnectionString"
   connectionString="Data Source=.;Initial Catalog=Databasename;User ID=;Password="
providerName="System.Data.SqlClient" />
</connectionStrings>
<appSettings>
   <add key="Source" value="C:\Document"/>
   <add key="Destination" value="D:\Google"/>
   <add key="IsManualUpdate" value="true"/>
</appSettings>
</configuration>

Add in Code behind:

SourcePath = ConfigurationSettings.AppSettings["Source"];
DestinationPath = ConfigurationSettings.AppSettings["Destination"];