I stucked at this error...

Code:
//Code
 FileStream fs = new FileStream(
               @"D:\Sagar Dot Net\Assign_2304_Interface_Person_Serialise\Assign_2304_Interface_Person_Serialise\Aadmai.txt",
               FileMode.OpenOrCreate,
               FileAccess.Read);
            BinaryFormatter bf = new BinaryFormatter();
            object obj = bf.Deserialize(fs);
            if (obj is
...