Xbasic

Type Checking Functions

Description

Determine type of data.

Name
Description
ISALPHA Function

Returns TRUE if the first character of a string is a letter.

ISDATE Function

Returns .T. if Date is a valid date.

ISDIGIT Function

Returns TRUE if the first character of a string is a digit.

ISLOWER Function

Returns TRUE if the first character of a string is lowercase.

ISNOTBLANK Function

Returns TRUE if the field is not blank.

ISNULL Function

Tests if a string is empty or contains only whitespace.

ISNUMBER Function

Returns .t. if a text string contains only numbers

IsShortTime Function

Returns true is the string value is a valid short time.

ISTIME Function

Returns true is the string value is a valid datetime.

ISUPPER Function

Returns TRUE if the first character of a string is uppercase.

Related Functions

ISALPHA() - Returns . T. (TRUE) if the first character of the specified Character_String is a letter; otherwise, returns .F. (FALSE).

ISBLANK() - Returns .T. (TRUE) if the field identified in the Field_Name is blank; otherwise, it returns .F. (FALSE).

ISDATE() - Returns .T. (TRUE) if Date_String is a valid date; otherwise, returns .F. (FALSE).

ISNUMBER() - Returns .T. if a character string contains only numbers; otherwise, returns .F. (FALSE).