how to check if the string's format is alphabetical or numeric

[lotos]

hi all,
I have an issue with string formats.
As a result of some queries within DB I am getting or text values or numeric values assigned to my string, for e.g:
str_Value = Y
or
str_Value = 123

how can I check if "str_Value" is numeric or text format?!

The idea is that if it is a numeric format, I should change it's format:

Code:

str_Value = FormatNumber(str_Value, 2)

if not It will remain as it is within DB (text)