Stealing" earthandfire's suggestion, do also try with "numbers" like this:
[tt]dim a as string
a = "1E1" ' <- note the letter E ("Scientific" notation)
if IsNumeric(a) then
messagebox.show("yes")
else
messagebox.show("no")
end if[/tt]
If the above scenario is a possibility, then I'd suggest other approaches than IsNumeric. Combine IsNumeric with looping the string, Regex ... Here's one thread with some discussions and suggestions thread796-1104616
(here's discussion from the VB5/6 forum with some history too, should it be interesting thread222-1071392)
Here's an attempt that might work, if the string must contain only digits.
[tt] Dim strNum As String = "234E34"
Dim lngCount As Long
Dim lngLen As Long = strNum.Length - 1
For lngCount = 0 To lngLen
If (Not Char.IsDigit(strNum, lngCount)) Then
MessageBox.Show("contains text")
End If
Next lngCount[/tt]
Roy-Vidar