Problem getting node

[John Wilhelm]

I'm having a problem in by VB.net 2005 application. When i try to get a node
from my app.config file the node come back with "nothing". The xmldocment
loads OK, but I can't retrive a node. The app.config file is listed below
and the code is listed below that, the line with "-->>" is where i try to
get the node. Can anyone see where I'm going wrong.

A dump of the xmlDocument is listed below the code.
Note: "MyKey" is set to "Reports"

Thank,
John
jo***@iirp.coedu.usf.edu
App.config file
----------------------------------------------------------------------------------
<?xml version="1.0"?>
<configuration xmlns="http://schemas.microsoft.com/.NetConfiguration/v2.0">
<configSections>
</configSections>
<connectionStrings>
<add name="My.MySettings.DataConnectionString"
connectionString="Provider=Microsoft.Jet.OLEDB.4.0 ;Data
Source=C:\Ingredients_Data.mdb" providerName="System.Data.OleDb" />
</connectionStrings>
<appSettings>
<add key="Reports" value="C:\current\Reports.xls" />
<add key="Calendar" value="C:\current\Calendar.xls" />
<add key="ClaimContinuum"
value="C:\current\ClaimContinuumReportBuild.xls" />
</appSettings>
</configuration>
----------------------------------------------------------------------------------
----------------------------------------------------------------------------------
Public Function Save_Config_Parameter(ByVal MyKey As String, ByVal MyValue
As String) As String

Dim XmlDocument As New XmlDocument
Dim XmlNode As XmlNode
Dim XmlRoot As XmlNode
Dim XmlKey As XmlNode
Dim XmlValue As XmlNode

Save_Config_Parameter = ""
XmlDocument.Load(AppDomain.CurrentDomain.SetupInfo rmation.ConfigurationFile)--->> XmlNode =XmlDocument.DocumentElement.SelectSingleNode("//configuration/appSettings/add[@key=""" & MyKey & """]") If XmlNode Is Nothing Then ' The node does not exist, let's create it XmlNode = XmlDocument.CreateNode(XmlNodeType.Element, "add", "") ' Adding the Key attribute to the node, keep in mind, Xml tokens are casesensitive ' We should use 'key' instead of 'Key' XmlKey = XmlDocument.CreateNode(XmlNodeType.Attribute, "key", "") XmlKey.Value = MyKey XmlNode.Attributes.SetNamedItem(XmlKey) ' Adding the key value, once again, remember that Xml tokens are casesensitive XmlValue = XmlDocument.CreateNode(XmlNodeType.Attribute, "value", "") XmlValue.Value = MyValue XmlNode.Attributes.SetNamedItem(XmlValue) ' Add the new node to the root XmlRoot =XmlDocument.DocumentElement.SelectSingleNode("/configuration/appSettings") If Not XmlRoot Is Nothing Then XmlRoot.AppendChild(XmlNode) Else Save_Config_Parameter = "ERROR" End If Else ' ' The node exist, save the new value ' XmlNode.Attributes.GetNamedItem("value").Value = MyValue End If XmlDocument.Save(Application.ExecutablePath & ".config") XmlDocument = NothingEnd Function========================================== =============================>? XmlDocument{System.Xml.XmlDocument} Attributes: Nothing BaseURI: "file:///C:/John/bin/Debug/App.vshost.exe.config" ChildNodes: {System.Xml.XmlChildNodes} DocumentElement: {System.Xml.XmlElement} DocumentType: Nothing FirstChild: {System.Xml.XmlDeclaration} HasChildNodes: True Implementation: {System.Xml.XmlImplementation} InnerText: "" InnerXml: "<?xml version="1.0"?><configurationxmlns="http://schemas.microsoft.com/.NetConfiguration/v2.0"><configSections></configSections><connectionStrings><addname="My.MyS ettings.DataConnectionString"connectionString="Pro vider=Microsoft.Jet.OLEDB.4.0;DataSource=C:\Ingred ients_Data.mdb" providerName="System.Data.OleDb"/></connectionStrings><appSettings><add key="Reports"value="C:\current\Reports.xls" /><add key="Calendar"value="C:\current\Calendar.xls" /><add key="ClaimContinuum"value="C:\current\ClaimContinu umReportBuild.xls"/></appSettings></configuration>" IsReadOnly: False Item: In order to evaluate an indexed property, the property must bequalified and the arguments must be explicitly supplied by the user. LastChild: {System.Xml.XmlElement} LocalName: "#document" Name: "#document" NamespaceURI: "" NameTable: {System.Xml.NameTable} NextSibling: Nothing NodeType: Document {9} OuterXml: "<?xml version="1.0"?><configurationxmlns="http://schemas.microsoft.com/.NetConfiguration/v2.0"><configSections></configSections><connectionStrings><addname="My.MyS ettings.DataConnectionString"connectionString="Pro vider=Microsoft.Jet.OLEDB.4.0;DataSource=C:\Ingred ients_Data.mdb" providerName="System.Data.OleDb"/></connectionStrings><appSettings><add key="Reports"value="C:\current\Reports.xls" /><add key="Calendar"value="C:\current\Calendar.xls" /><add key="ClaimContinuum"value="C:\current\ClaimContinu umReportBuild.xls"/></appSettings></configuration>" OwnerDocument: Nothing ParentNode: Nothing Prefix: "" PreserveWhitespace: False PreviousSibling: Nothing SchemaInfo: {System.Xml.Schema.XmlSchemaInfo} Schemas: {System.Xml.Schema.XmlSchemaSet} Value: Nothing>

[dickster]

Hi John

The problem I believe lies in the fact that your XML falls under the
default namespace
xmlns="http://schemas.microsoft.com/.NetConfiguration/v2.0"

And your xpath expression is not namespace aware.

That is why your Xpath expression doesn't work as you hope - i.e
XmlNode =
XmlDocument.DocumentElement.SelectSingleNode("//configuration/appSettings/add[@key="""
& MyKey & """]")

i.e this always sets XmlNode to null

A quick work around would be to remove the namespace from your Xml to
get your code rolling and xpath working.

- however as has been quoted elsewhere on this group
"Changing the XML to remove xmlns is usually not the right way to solve
the problem but rather an attempt to circumvent the problem."

For more info on namespaces & xpath in .NET read:
Article by Martin Honnen -
http://www.faqts.com/knowledge_base/.../34022/fid/616
&
"XPath Queries with Namespaced Mapped Prefixes" in MSDN

Dickster