I often need to include a timestamp in a build, either in naming a file or folder produced during the build, or using it in the content of a file.

MsBuild has built-in property functions that allow this to be fairly painless once you are familiar with the syntax.

The syntax for calling static methods is:

$([Namespace.Type]::Method(parameters if required go here))

The syntax for static properties is:

$([Namespace.Type]::Property)

So you can generate a new guid during a build using:

$([System.Guid]::NewGuid().ToString())

Here's a timestamp in ISO 8601 format.

<_BuildDateAndTime>$([System.DateTime]::Now.ToString(yyyy-MM-ddThhmmss))</_BuildDateAndTime>