The amount of help you can find on the web about binding a datasource to a datagrid is astounding. Once you bound your datagrid and populated it, the user of course wants to see it.

They may optionally want to update, delete or insert data into your nicely bound datagridview.

All of the above is well documented on the web and easy to pull off. So now what?

Let's suppose you want to "Do" something with the data, say.... save it back to a source?

Well if you were using an unbound datasource and populated it on the fly, AND thought you could persist some data in hidden columns, you are sadly mistaken.

The data in hidden columns is never bound on the databind(). That’s right, a predefined column with the datafield attribute set and the visible attribute set false will not bind to the datasource datafield.

The trick is to define all columns of data you wish to persist to visible columns and then after you call the databind(), hide the columns you don't want to show the user. The data will now persist.

CAUTION! If you rebind (update the datagrid datasource) after you've hidden the columns, the data will be lost again. You must first make the columns visible again, then rebind the datagrid and then you may hide the columns once more.

Speeding up Vista with ReadyBoost USB RAM drive

I personally am not running any Vista PCs or notebooks (don't have the hardware base). But if anyone is experiencing the Vista hardware drain, Alec Saunders has blogged a bit on his experience with ReadyBoost included with Microsoft Windows Vista.

I'd love to know if anyone else has had positive results with it.

Speeing up Windows Vista http://saunderslog.com/2007/04/02/speeding-up-windows-vista/

InfoPath goes to XML Schemaville

OK, in XML schemaville, when you define an element (<xsd:element></xsd:element>) you define the the type of element it is and what type of children it will contain (text or other xml elements) if you want it to do both (contain text nodes and element nodes) you have to explicitly define it like that typically you define element nodes that contain child element nodes to not contain text nodes as well.

In InfoPath, elements that contain other child elements are called "groups". The IP schema tool does support defining mixed content nodes. So, since your target node is a "group" it is not allowed to contain text. You must either change it to an element (remove group & re-add element by same name) or do not write to it (add a child element to it to write to) .

Generate Xpath Statement

Ever want to work out what the Xpath statement would be for a current node of an XML document? Well here you go. This little tid bit will quickly work its way back up the parent-grandparent tree, up to the root node of the document. And when it's done, you'll be returned the Xpath statement.

Code: (generated for InfoPath C# managed code)

private string GenerateMatchPath(IXMLDOMNode sourceNode, string xPath)
{
IXMLDOMNode parentNode = sourceNode.parentNode;
while (parentNode != null && parentNode.nodeName != "#document")
{
xPath = parentNode.nodeName + "/" + xPath;
parentNode = parentNode.parentNode; } return "/" + xPath;
}//GenerateMatchPath

Now, why would this be useful?

Suppose you would like to compare the data of a pair of XML documents (docA and docB).

If you used an Xpath query (xmlDoc.selectNodes("//descendant-or-self::node()")) to generate a nodelist of all elements in docA, you could:

• loop through each node from docA
• get its value
• generate the xpath
• use the xpath to get the value from docB
• compare values
• take appropriate action (update docA? update docC?)

[Snippet to follow...]

Clearing Windows network passwords.

I have recently found problems with my Visual Source Safe 2005 (VSS) solution bindings breaking in Visual Studio .NET 2005 (VS2005). On two occassions in the last week I have encountered "Invalid Handle" errors when trying to check-in my solutions.

The invalid handle error is due to the VSS bindings. The solution has been to restablish the bindings, however, this was hampered by the root problem ;) Somehow a bad password was saved, and the connection to the VSS server could not be established. So, the corrupt credentials must be removed.

To do this, I found James Geurts' Blog on 'Clear saved windows networking passwords' where he supplies the following:

Start>Run>rundll32.exe keymgr.dll, KRShowKeyMgr

The same dialog can be opened via:

Start>Control Panel>User Accounts>Advanced Tab>Manage Passwords

I prefer the latter option as it is easier to remember and find again ;)

(James Geurts' Blog http://biasecurities.com/blogs/jim/archive/2005/12/20/3876.aspx)