Determines whether an expression is blank.
Syntax
ISBLANK(eExpression)
Returns
Logical
Arguments
eExpression
Specifies the expression that ISBLANK( ) evaluates. eExpression can be a field in a table, a variable or array element, or an expression.
For a field, ISBLANK( ) returns true (.T.) if the field contains the following values.
| Type | Contents |
| Character | Empty string, spaces, or no value (newly appended blank record or cleared with BLANK) |
| Numeric | No value (newly appended blank record or cleared with BLANK) |
| Float | No value (newly appended blank record or cleared with BLANK) |
| Date | Blank date ({ / / }) or no value (newly appended blank record or cleared with BLANK) |
| DateTime | Blank datetime ({ / / : : }) or no value (newly appended blank record or cleared with BLANK) |
| Logical | No value (newly appended blank record or cleared with BLANK) |
| Memo | Empty (no memo contents) |
| General | Empty (no OLE object) |
| Picture | Empty (no picture) |
Remarks
ISBLANK( ) returns true (.T.) if the expression eExpression is blank; otherwise, ISBLANK( ) returns false (.F.).
APPEND BLANK and BLANK are used to create a blank record. BLANK can also be used to clear data from fields in a record. ISBLANK( ) can determine if a field is blank.
Note that Currency, Integer and Double type expressions are never blank, and ISBLANK( ) always returns false (.F.) for these data types.
ISBLANK( ) differs from EMPTY( ) and ISNULL( ). For example, EMPTY( ) returns true (.T.) if a character expression contains any combination of null values, spaces, tabs, carriage returns, or line feeds; ISBLANK( ) returns true (.T.) if a character expression contains only the empty string or spaces.