Top 20 NuGet appconfig Packages

Injects values into config files directly or via environment variables. Can inject app settings, connection strings, or WCF client endpoints.
Mimick AppConfig adds support for configuration sources from standard or custom application configuration files.
F# Libary for managing configuration data from environment variables and application config in a type-safe way
Configuration service for .NET Apps.
Adds DataObjects.Net configuration template and configuration file schema
Config plugin to Xamarin.Forms, Xamarin.Android and Xamarin.iOS applications.
This solution assigned for easy development of any application by ASP NetCore EntityFramework in one-context SQL infrastructure. See GitHub.
AppSettings class mapper.
DotNet Development Utilities. Autoreader AppConfig file.
A Photon plugin for modifying and transforming VS App/Web config files.
SimplifiedConfiguration makes it a breeze to read the config file settings. It's APIs makes it unnecessary to specify the app settings key and rather derive the key from the property name.
.Net Dev Utils
A lightweight library to load application configuration settings into a dictionary.
Wrapper class library for WinRT Roamin/Local settings.
Allows to generate app.config file from configuration class
A micro-module for parsing configuration values from App.config and other .NET configuration files. Feel free to bundle this module with your core library (using any packer, like ILMerge, ILRepack, LibZ, etc.), use micro-assembly as it is, or just take the source code and use it in your project.
A micro-module for parsing JSON configuration values from App.config and other .NET configuration files. Feel free to bundle this module with your core library (using any packer, like ILMerge, ILRepack, LibZ, etc.), use micro-assembly as it is, or just take the source code and use it in your projec...
Simple syntactic sugar for ConfigurationManager
Easily manage configuration within your .net application
This Configuration Reader simplify the multiple configuration saved in the Windows Registry, sent by Command Line, included in App.Config or recorded in a database table.