can we do this in regular expression?

[JayJayson]

Hi,

You will struggle to do this without looking over your sentence more than once. Regex cannot step backwards to look at substrings that have already been matched.

If you would like to stick with Regex then you could do something like this:

Dim str As String = "This is a test"
Dim str2 As String = str.Remove(0, str.IndexOf(" ") + 1)
 
Dim Results As MatchCollection = Regex.Matches(str, "\b\w+\b\s?\b\w+\b")
Dim Results2 As MatchCollection = Regex.Matches(str2, "\b\w+\b\s?\b\w+\b")
 
Dim output As String = Nothing
 
For i As Integer = 0 To Results.Count - 1
    output += Results.Item(i).Value & vbCrLf
    If i <= Results2.Count - 1 Then
        output += Results2.Item(i).Value & vbCrLf
    End If
Next
 
MsgBox(output)

Although you should be able to write a better function to achieve the same goal using different methods e.g. String.Split, For-Next and Concatenation.

Hope this helps