The ISALPHA function checks that an expression consists entirely of alphabetic characters.
NOTE: This function is only available in jBASE 4.1 and later.
expression can return a result of any type. The ISALPHA function will then return TRUE (1) if the expression consists of entirely alphabetic characters. The function will return FALSE (0) if any character in the expression is not alphabetic.
When the ISALPHA function is used in International Mode the properties of each character are determined according to the Unicode Standard.