The VersionInfo property is longer text, usually shown in a change log, describing the changes made to the item since last version. The text is represented as a zlib compressed utf-16 xml string. It is of type byte[]. This article describes how to convert the byte[] to a string. 

Use SystemWeaver.Common.Internal.SWCompression.ZCompressStringToBytes(System.String) and SystemWeaver.Common.Internal.SWCompression.ZDecompressToString(System.Byte[]) to convert to and from the byte array given by the API and the actual string value.

Example

IswItem v = SWConnection.Instance.Broker.GetItem(SWHandleUtility.ToHandle("x0400000000000020"));
byte[] versionInfoByteArray = v.VersionInfo;        
string versionInfoString = SystemWeaver.Common.Internal.SWCompression.ZDecompressToString(versionInfoByteArray);