System.configuration.configurationmanager Version 4.0.1.0 ^hot^ Direct

: Access data from appSettings and connectionStrings using the ConfigurationManager class.

Unlike Microsoft.Extensions.Configuration (which is read-only by design), this package still supports Save() on configuration files. If you need a user settings file that persists changes back to disk, this works out of the box. system.configuration.configurationmanager version 4.0.1.0

The error message often looks like this: : Access data from appSettings and connectionStrings using

: If you are porting a .NET Framework library to .NET Standard 2.0 but still need to support older applications that rely on app.config , this version acts as the bridge. The error message often looks like this: :

Always add null checks:

While .NET Core introduced a new, more flexible configuration system ( Microsoft.Extensions.Configuration ), the demand for backward compatibility remained high. Developers porting libraries to .NET Core wanted their existing ConfigurationManager code to work without rewriting the entire configuration layer.