manipulating a string

I have a string like so:
hey how are you

I want to change it so its like this:
hey *how are you

with the asterisk after the 1st space. I would like to know the best way to do this. Thanks in advance.

Did it myself thanks.

VB Code:

Private Sub Command1_Click()
 
Dim intPos As Integer
Dim str As String
Dim strStore As String
 
str = Text1.Text
 
intPos = InStr(1, str, " ", vbTextCompare)
 
If intPos > 0 Then
    ' store string after space
    strStore = Right$(str, Len(str) - intPos)
    ' place asterisk after first space
    Mid$(str, intPos + 1) = "*"
End If
 
Text2.Text = Left$(str, intPos + 1) & strStore
 
End Sub
 
Private Sub Form_Load()
 
Text1.Text = "Enter a string"
Text2.Text = ""
 
End Sub

place 2 textboxes and a command button on a form