added extension method for System.Text.Encoding to support better use of spans in modern frameworks

Author: Crypt32

Asn1Parser/Utils/CLRExtensions/EncodingExtensions.cs

@@ -0,0 +1,24 @@
+using System;
+using System.Text;
+
+namespace SysadminsLV.Asn1Parser.Utils.CLRExtensions;
+
+/// <summary>
+/// Provides extension methods for the <see cref="System.Text.Encoding"/> class to enhance its functionality.
+/// </summary>
+static class EncodingExtensions {
+    /// <summary>
+    /// Decodes a sequence of bytes from the specified <see cref="ReadOnlyMemory{T}"/> into a string using the provided <see cref="System.Text.Encoding"/>.
+    /// </summary>
+    /// <param name="encoding">The <see cref="System.Text.Encoding"/> to use for decoding the byte sequence.</param>
+    /// <param name="bytes">The byte sequence to decode, represented as a <see cref="ReadOnlyMemory{T}"/> of <see cref="Byte"/>.</param>
+    /// <returns>A <see cref="String"/> that contains the decoded characters from the byte sequence.</returns>
+    /// <exception cref="ArgumentNullException">Thrown if <paramref name="encoding"/> is <c>null</c>.</exception>
+    public static String GetString(this Encoding encoding, ReadOnlyMemory<Byte> bytes) {
+#if NET8_0_OR_GREATER
+        return encoding.GetString(bytes.Span);
+#else
+        return encoding.GetString(bytes.ToArray());
+#endif
+    }
+}