Save DataGridView to XML

Question

Hello All
This issue has got to do with saving and retrieving data from xml into DataGridViews and vice versa
My xml file would look like this
 
<?xml version="1.0" encoding="utf8" ?>
 <TestDescription xmlns:xsi="http://www.w3.org/2001/XMLSchemainstance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" DeviceName="Three phase meter1" DeviceType="DeltaPlus1" DescriptionId="79AB314238CD423dA0CB4D49D3E75F13" Status="NotStarted" Version="1.0" TimeStamp="20021010T02:00:00+05:30" xmlns="urn:DeviceTestDescription">
 <CommunicationDescription>
<PhysicalMedia>RS232</PhysicalMedia>
<CommunicationProtocol>Modbus</CommunicationProtocol>
<DeviceAddress>1</DeviceAddress>
<CommunicationPort>1</CommunicationPort>
<BaudRate>4800</BaudRate>
<HandShake>XON</HandShake>
</CommunicationDescription>
 <TestSuite>
 <TestGroup ID="1001" Description="Group1" ErrorCondition="Skip">
 <TestCase ID="1001" Description="CT">
 <TestStep Command="SetCT" ID="" Description="Set CT">
 <Parameters>
<Parameter Name="setCTRatio" Value="8232" Direction="Write" />
</Parameters>
</TestStep>
 <TestStep Command="ReadCT" ID="" Description="Get CT">
 <Parameters>
<Parameter Name="getCTRatio" Direction="Read" />
</Parameters>
</TestStep>
<ValidationCriteria>if setCTRatio == getCTRatio testResult.valid = true else testResult.valid = false end</ValidationCriteria>
<ValidationError />
</TestCase>
</TestGroup>
</TestSuite>
<Log>Test Executed by : User1 Test Type : FTTPOC Remarks : DEMO version. Usage permitted for demonstration purposes only.</Log>
</TestDescription>
 
As you see above there are sections for Descriptions , CommunicationDescription, TestSteps and TestParamters
For each of the above sections i have a separate data grid view  and a separate dataset (ds , ds1, ds2, ds3) in my app. I am able to populate the data grid views properly but i am unable to save the modified datagridview into xml . How should i do this ? And since the data is spread over many data grid views , this is more confusing coz i have many data sets each pertaining to one datagridview.
I made a few changes to the "communicationDescription" and used  "ds1.AcceptChanges() ". It did not save . Using WriteXML () did save but the file got completely erased . Check my code .. Dont think it is any where close to correct

 
if (ds1.HasChanges() || ds2.HasChanges() || ds3.HasChanges() || ds.HasChanges())
{
DescriptionMode mode = (DescriptionMode)Enum.Parse(typeof(DescriptionMode), CurrentNavigation);
string[] files = Directory.GetFiles("D:\\TFS\\Code Snippets\\TestController\\TestController\\bin\\Debug\\" + mode.ToString(), "*.xml");
String file = files[overviewClickedRowIndex];
ds1.WriteXml(file);
ds2.WriteXml(file);
ds3.WriteXml(file);
ds.WriteXml(file);
}

Any help will be greatly appreciated. Thanks! Please respond asap..
AVink