<PackageReference Include="System.Configuration.ConfigurationManager" Version="9.0.0-preview.6.24327.7" />

ConfigXmlDocument

Wraps the corresponding XmlDocument type and also carries the necessary information for reporting file-name and line numbers.
using System.Collections; using System.Collections; namespace System.Configuration { public class ConfigurationLocationCollection : ReadOnlyCollectionBase { public ConfigurationLocation this[int index] { get { return (ConfigurationLocation)base.InnerList[index]; } } internal ConfigurationLocationCollection(ICollection col) { base.InnerList.AddRange(col); } } }