Tag Archives: visual basic

TFS API: How to Get a Specific Version Programmatically

Within the Visual Studio Source Control Explorer, there are a number of options available for getting files out of TFS. Often times, developers just want to get the latest code to work with. But in some scenarios, developers need to get source files based on alternate criteria, such as by a specific date or label.  TFS provides a handful of options for selecting source files easily within the “Get Specific Version” dialog.

TFS: Get Specific Version Options

This works really well within Visual Studio, but how can you do this programmatically?  As it turns out, the Workspace.Get() method has an overloaded method that takes a VersionSpec argument.  Notice that VersionSpec is actually a base class. and that there are several inherited classes that can be used to specify the changeset type, including:

  • ChangesetVersionSpec
  • DateVersionSpec
  • LabelVersionSpec
  • LatestVersionSpec (equivalent to VersionSpec.Latest)
  • WorkspaceVersionSpec

For example, if you wanted to perform a GET on a specific changeset, you would simply pass an instance of ChangesetVersionSpec:

'connect to source control and get reference to existing workspace
Dim server As TfsTeamProjectCollection = _
Dim vcs As VersionControlServer = _
   server.GetService(Of VersionControlServer)()
Dim ws As Workspace = vcs.GetWorkspace("MyExistingWorkspace", My.User.Name)

'Perform a GET on Changeset 100
Dim version As New ChangesetVersionSpec(100)
ws.Get(version, GetOptions.GetAll)

Performing a GET based on a pre-defined label works in much the same way (just replace the ChangesetVersionSpec object with a LabelVersionSpec object):

'connect to source control and get reference to existing workspace
' (same as above)...

'Perform a GET on items defined by label "My Label"
Dim version As New LabelVersionSpec("My Label")
ws.Get(version, GetOptions.GetAll)

Updated 2/28/2012: Revised code sample for TFS 2010 API.

TFS API: Check if Server Path Exists

Disclaimer:  Rarely do I get a chance to totally geek out and write a post specifically about code.  I enjoy the change-up.  And hopefully some of you will benefit from this.

Ok.  On a recent project, I’ve been playing around with the .NET APIs that were made available for interacting with TFS. You can tell that the documentation for these API’s are a little more raw than what is available for the .NET framework components, but that is not to say they aren’t still helpful.

As part of my project, I needed to programmatically download files to the local machine from version control.  As part of my unit testing, I wanted to validate the source path before attempting the download.  Basically, I wanted the equivalent of the System.IO.Directory.Exists() method in the .NET framework, but that validates against version control.

After several minutes of searching, I found the VersionControlServer.ServerItemExists() method. This handy method basically combines the functionality of the File.Exists() and Directory.Exists() methods, switching between the two (or combining) by setting the custom ItemType enumeration.

Using this method, I can first validate the path, as the following example shows:

Dim fakePath As String = "$/MyFakeTeamProject/RoadToNowhere"
Dim vcServer As VersionControlServer = Nothing

'...initialize a reference to the version control server here...

'Perform validation against server path before downloading.
' This example works for both file or directory paths.
If Not vcServer.ServerItemExists(fakePath, ItemType.Any) Then
   Throw New Exception("Hey! The path you gave me is bunk!")
End If

…and for the C# folks:

string fakePath = "$/MyFakeTeamProject/RoadToNowhere";
VersionControlServer vcServer = null;

//...initialize a reference to the version control server here...

// Perform validation against server path before downloading.
//  This example works for both file or directory paths.
if (!vcServer.ServerItemExists(fakePath, ItemType.Any))
   throw new Exception("Hey! The path you gave me is bunk!");

MSDN Article: Using XML Comments

The May 2009 MSDN Magazine has a good article reviewing XML comments and their usefulness for code development and documentation.  The article is primarily written for VB developers, but the concepts do apply to C# developers as well.

I’ve been using XML comments since Visual Studio 2005 came out.  For your VB developers still developing legacy .NET 1.1 / VS 2003 apps, you can install the VBCommenter add-in, which will give you some of the basic functionality (C# developers have this out-of-the-box).

If you’re not familiar with XML comments – or if you’ve heard of them, but haven’t tried them out yet – give the article a look.

A Coder’s Challenge

I was recently “challenged” by a fellow agile member who claimed that Java developers have a higher maturity level then their fellow .NET developers.  His claim was that .NET developers rely too much on the mouse when programming, which makes them slower because their hands have to leave the keyboard more frequently.  Java developers, on the other hand, are more familiar with their tool (e.g. IDE) and all the keyboard shortcuts that are programmed into it.

So, I considered his claims and his challenge.  I scoured the interwebs, searching for the knowledge I sought that would help me master the .NET coder’s tool of choice (the great Visual Studio), until I found what I was looking for.

And so, for my fellow .NET “adolescents”, I share with you this, straight from our god herself:

You threw down the gauntlet, B.C. and I accept your challenge.