Start porting some functionality

SabreTools.Serialization/Wrappers/InstallShieldCabinet.cs

@@ -87,6 +87,15 @@ namespace SabreTools.Serialization.Wrappers
 
         #endregion
 
+        #region Extraction State
+
+        /// <summary>
+        /// Base filename path for related CAB files
+        /// </summary>
+        private string? _filenamePattern;
+
+        #endregion
+
         #region Constants
 
         /// <summary>
@@ -238,6 +247,14 @@ namespace SabreTools.Serialization.Wrappers
             return set;
         }
 
+        /// <summary>
+        /// Open the numbered cabinet set volume
+        /// </summary>
+        /// <param name="volumeId">Volume ID, 1-indexed</param>
+        /// <returns>Wrapper representing the volume on success, null otherwise</returns>
+        public InstallShieldCabinet? OpenVolume(ushort volumeId)
+            => OpenVolume(_filenamePattern, volumeId);
+
         /// <summary>
         /// Open the numbered cabinet set volume
         /// </summary>
@@ -271,6 +288,15 @@ namespace SabreTools.Serialization.Wrappers
             return volume;
         }
 
+        /// <summary>
+        /// Open a cabinet file for reading
+        /// </summary>
+        /// <param name="index">Cabinet part index to be opened</param>
+        /// <param name="suffix">Cabinet files suffix (e.g. `.cab`)</param>
+        /// <returns>A Stream representing the cabinet part, null on error</returns>
+        public Stream? OpenFileForReading(int index, string suffix)
+            => OpenFileForReading(_filenamePattern, index, suffix);
+
         /// <summary>
         /// Open a cabinet file for reading
         /// </summary>