How to get Microsoft.Office.Project.Server.Library.ByteArray method?

Hello:

This is my code in projectserver2010, but after upgrading to 2013, this method can not be used.

 AssemblyName assemblyName = new AssemblyName("Microsoft.Office.Project.Server, Version=14.0.0.0, Culture=neutral, PublicKeyToken=71e9bce111e9429c");
                //加载dll
                Assembly assembly = Assembly.Load(assemblyName);
                //实例任务日志修改对象
                changeLogType = assembly.GetType("Microsoft.Office.Project.SvrDataEdit.ChangeLog");
                changeType = assembly.GetType("Microsoft.Office.Project.SvrDataEdit.Change");
                //选择要调用的方法
                fromBytesMethod = changeLogType.GetMethod("FromBytes");

                Object obj = fromBytesMethod.Invoke(null, new object[] { new Microsoft.Office.Project.Server.Library.ByteArray(rtfbytes) });
                int count = (int)changeLogType.InvokeMember("Count", BindingFlags.Default | BindingFlags.GetProperty, null, obj, null);

                //操作详细信息

Namespace  Microsoft.Office.Project.Server.Library does not exist type or namespace " nameByteArray"

How can I use nameByteArray method  in projectserver2013  ?