>George,
>
>IsDigit() checks only first symbol, so it's not suitable for my situation. Type() works fine.
>
>Example:
>
>myNumber='12345'
>type(myNumber)='N'
>isDigit(myNumber)=.t.
>
>myNumber='1hffhhf'
>type(myNumber)='U'
>isdigit(myNumber)=.t.

Nadya,

This behavior is not in accordance with the docs. Whether or not it's a bug, I don't know. The TYPE() function, according to the documentation, should receive a character expression, not a variable. If this behavior is a bug, in may be corrected in a future service pack or release. If this does happen, it may cause problems for you in the future.

While ISDIGIT() does only check the first character in a multi character string, there's nothing to keep you from looping through and using it to check each character via SUBSTR() like this:

llisnumber = .T.
lni = 1
DO WHILE llisnumber AND (lni <= LEN(mystring))
  llisnumber = ISDIGIT(SUBSTR(mystring, lni, 1))
  lni = lni + 1
ENDDO
RETURN llisnumber