string xmlStr = "<doc><assembly><name>XMLdoc</name></assembly></doc>";
DataSet dataSet = new DataSet();
dataSet.ReadXml(new System.IO.MemoryStream(System.Text.Encoding.Default.GetBytes(xmlStr)));
DataSet dataSet = new DataSet();
dataSet.ReadXml(new System.IO.MemoryStream(System.Text.Encoding.Default.GetBytes(xmlStr)));