XML and Binary File Read Write

public static bool WriteXML<T>(string fileName, IEnumerable<T> objList)
        {
            DataContractSerializer x = new DataContractSerializer(new ObservableCollection<T>().GetType());
            FileStream writer = new FileStream(fileName, FileMode.Create);
            x.WriteObject(writer, objList);
            writer.Flush();
            writer.Close();
            writer.Dispose();
            return true;
        }

        public static void ReadXML(string fileName)
        {
            /*here object means your business object*/
            FileStream fs = new FileStream(fileName, FileMode.Open);
            XmlDictionaryReader reader = XmlDictionaryReader.CreateTextReader(fs, null);
            DataContractSerializer ser = new DataContractSerializer(typeof(Object));

            // Deserialize the data and read it from the instance.
            Object deserialized = (Object)ser.ReadObject(reader, true);
            reader.Close();
            fs.Close();
        }

        public bool CreateXML<T>(List<T> objList, string fileName)
        {
            string path = fileName + ".xml";
            XmlSerializer x = new XmlSerializer(new List<T>().GetType());
            StreamWriter writer = new StreamWriter(path);
            x.Serialize(writer, objList);
            writer.Flush();
            writer.Close();
            writer.Dispose();
            return true;
        }

        public void ReadXML(string fileName)
        {
            DataSet ds = new DataSet();
            System.IO.FileStream fs = new System.IO.FileStream(fileName, System.IO.FileMode.Open);
            ds.ReadXml(fs);
            fs.Close();
            fs.Dispose();
        }

public bool CreateBinaryDataFile<T>(List<T> objList, string xmlFileName)
        {
            using (FileStream str = File.Create(xmlFileName))
            {
                BinaryFormatter bf = new BinaryFormatter();
                bf.Serialize(str, objList);
                str.Flush();
                str.Close();
                str.Dispose();
            }
            return true;
        }

        public bool ReadBinaryDataFile(string xmlFileName)
        {
            string myXMLfile = @"D:\" + xmlFileName;
            List<object> _IssueList = new List<object>();
            using (FileStream str = File.OpenRead(myXMLfile))
            {
                BinaryFormatter bf = new BinaryFormatter();
                _IssueList = (List<object>)bf.Deserialize(str);
                str.Flush();
                str.Close();
                str.Dispose();
                return true;
            }
        }