visual studio 2008 - Is there an easy way to randomize a list in VB.NET?

Question

I have a list of type System.IO.FileInfo, and I would like to randomize the list. I thought I remember seeing something like list.randomize() a little while back but I cannot find where I may have seen that.

My first foray into this yielded me with this function:

Private Shared Sub GetRandom(ByVal oMax As Integer, ByRef currentVals As List(Of Integer))
    Dim oRand As New Random(Now.Millisecond)
    Dim oTemp As Integer = -1
    Do Until currentVals.Count = IMG_COUNT
        oTemp = oRand.Next(1, oMax)
        If Not currentVals.Contains(oTemp) Then currentVals.Add(oTemp)
    Loop
End Sub

I send it the max val I want it to iterate up to, and a reference to the list I want the randomized content in. The variable IMG_COUNT is set farther up in the script, designating how many random images I want displayed.

Thanks guys, I appreciate it :D

Answer 1

Check out the Fisher-Yates shuffle algorithm here: http://en.wikipedia.org/wiki/Knuth_shuffle

with a more concise discussion by this site's chief overlord here: http://www.codinghorror.com/blog/archives/001015.html

There is a simple C# implementation in the blog entry that should be real easy to change to VB.NET