LINQ to XML - Update and save a node to XML file

[Julie]

I have an XML file.I want to update (add some nodes) to it.Here is how the code looks:\[code\]var xmlDocuments = XDocument.Load(filePath);var documentElementToEdit = xmlDocuments.Element("Container").Element("Documents").Elements("Document").Where(x => x.Element("GUID").Value =http://stackoverflow.com/questions/11360574/= GUID).FirstOrDefault();missingIndexData1 = new XElement("IndexData");XElement indexData1 = new XElement("Name", "somename");XElement indexData2 = new XElement("Value", somevalue);XElement indexData3 = new XElement("DataType", "3");XElement indexData4 = new XElement("CreationTime", DateTime.Now.ToString("O"));XElement indexData5 = new XElement("CreationTimeUTC", DateTime.UtcNow.ToString("O"));missingIndexData1.Add(indexData1);missingIndexData1.Add(indexData2);missingIndexData1.Add(indexData3);missingIndexData1.Add(indexData4);missingIndexData1.Add(indexData5);documentElementToEdit.Element("IndexDatas").Add(missingIndexData1);documentElementToEdit.Save(filePath);\[/code\]What this does is that it overwrittes the original XML file with only this document node.How can I update the document node in the original file?