How to select the attributes?

[Sgt-Peppa]

Hey all, I have an xml File and need to read the attributes.

Heres my xml File:

<myRespRoot xmlns="http://myDatabaseAnswer/sql">
	<Schema name="Schema1" xmlns="urn:schemas-microsoft-com:xml-data" xmlns:dt="urn:schemas-microsoft-com:datatypes">
		<ElementType name="dbo.DataSets" content="empty" model="closed">
			<AttributeType name="IDNumber" dt:type="string" />
            <AttributeType name="ForeName" dt:type="string" />
            <AttributeType name="SureName" dt:type="string" />
            <AttributeType name="Street" dt:type="string" />
            <AttributeType name="PostalCode" dt:type="string" />
            <AttributeType name="City" dt:type="string" />
            <AttributeType name="DateOfBirth" dt:type="string" />
            <AttributeType name="Sex" dt:type="string" />
            <AttributeType name="Nationality" dt:type="string" />
            <AttributeType name="MothersBirthLastName" dt:type="string" />
            <attribute type="IDNumber" />
            <attribute type="ForeName" />
            <attribute type="SureName" />
            <attribute type="Street" />
            <attribute type="PostalCode" />
            <attribute type="City" />
            <attribute type="DateOfBirth" />
            <attribute type="Sex" />
            <attribute type="Nationality" />
            <attribute type="MothersBirthLastName" />
		</ElementType>
	</Schema>
	<dbo.DataSets xmlns="x-schema:#Schema1" IDNumber="P4711" ForeName="myName" SureName="myLastName" Street="myStreet" PostalCode="12345" City="myCity" DateOfBirth="01.01.1901" Sex="male" Nationality="German" MothersBirthLastName="myMothersBirthLastName" />
</myRespRoot>

Ok, what I am trying to do is to read the attributes IDNumber, Forename......
This is usually no problem but this time everytime I try to use this code:

XmlDocument myDoc = new XmlDocument();
myDoc.LoadXml(textBox1.Text);
textBox2.Text=myDoc.DocumentElement.SelectSingleNode("//dbo.PSI_DataSets").Attributes.GetNamedItem("IDNumber").InnerText.ToString();

I get the error saying Object reference not set to an instance of an object.

This even happens when I just try to get the SingleNode.
Anyone knows how to get to the attributes values?

Thanks,

Stephan