Dim txt As String = "+ 1.2990g"
Dim pattern As String = "(?<=\+).*?(?=g)"
Dim rgx = New System.Text.RegularExpressions.Regex(pattern, System.Text.RegularExpressions.RegexOptions.IgnoreCase)
For Each match As System.Text.RegularExpressions.Match In rgx.Matches(txt)
Output.Show(match.Value)
Next