problem updating a xml doc with AppendChild

[dratcha]

I am trying to insert new nodes within an existing XML document. The insert that I am having problems with is a few nodes deep. I can insert a new node just below the root node with the following with no problems: XmlDocument doc = new XmlDocument(); doc.Load(strXMLPath); XmlNode tasks = doc.SelectSingleNode("/tasks"); doc.AppendChild(tasks); // The rest of the AddElement and AddAttribute stuff has been omitted. Now, here is the code which tries to write a little deeper down and is breaking: XmlDocument doc = new XmlDocument(); doc.Load(strXMLPath); XmlNode checks = doc.SelectSingleNode("/tasks/task[@id='1001']/checks"); doc.AppendChild(checks); // The rest of the AddElement and AddAttribute stuff has been omitted. The error the second code snippet gives is: This document already has a DocumentElement node. It gives this error on the doc.AppendChild(checks); line I just can't figure it out. I did a quick watch on XmlNode checks = doc.SelectSingleNode("/tasks/task[@id='1001']/checks"); and it did put me in the correct node. I have no idea why I can not append into this node. Anyone have any ideas? Here is my XML doc if you want to see it for reference: <?xml version="1.0" encoding="utf-8"?> <tasks> <task id="1000"> <name>Task Name</name> <checks> <check id="1000_1"> <time>14:00</time> </check> <check id="1000_2"> <time>23:00</time> </check> </checks> </task> </tasks>

[rudy net]

Why would you want to append the same node that you queried? I would suggest the following: XmlNode checks = doc.SelectSingleNode("/tasks/task[@id='1001']/checks"); XmlNode newCheck,newNode; newCheck = doc.CreateElement("check"); XmlAttribute attr = doc.CreateAttribute("id"); attr.Value = "1000_3"; newCheck.Attributes.Append(attr); //add child node of new check newNode = doc.CreateElement("time"); newNode.Value = "15:00"; newCheck.AppendChild(newNode); checks.AppendChild(newCheck);