Expressions Reference
Chapter Updated 2/19/04
| Operand | Type | Function |
|---|---|---|
| + | Alpha | Concatonate |
| + | Numeric | Addition |
| - | Alpha | Concatonate, remove white space |
| - | Numeric | Subtraction |
| * | Numeric | Multiplication |
| / | Numeric | Division |
| ** | Numeric | Exponentiation |
| < | Logical | Less Than |
| > | Logical | Greater Than |
| = | Logical | Equal |
| <> | Logical | Not Equal |
| # | Logical | Not Equal |
| <= | Logical | Less Than or Equal |
| >= | Logical | Greater Than or Equal |
| $ | Logical | Contains |
| -> | N/A | Identifies database field ie; DATABASE->FIELD |
| .AND. | Logical | Logical AND |
| .OR. | Logical | Logical OR |
| Expression Function | Xbase C++ Method | Description |
|---|---|---|
| ABS() | xbDouble EXPN::ABS( xbDouble d ) | Returns absolute numeric value of argument. |
| ASC() | xbLong EXPN::ASC( char * String ) | Returns ASCII code of left character of string. |
| AT() | xbLong EXPN::AT( char *s1, char *s2 ) | Returns starting position of first alphanumeric argument in second argument. |
| CDOW() | char * EXPN::CDOW( char Date8 ) | Returns name of the day of the week of Date8. |
| CHR() | char * EXPN::CHR( xbLong l ) | Returns ASCII character corresponding to numeric value supplied. |
| CMONTH() | char * EXPN::CMONTH( char * Date8 ) | Returns name of the month of Date8. |
| DATE() | char * EXPN::DATE() | Returns system date. |
| DAY() | xbLong EXPN::DAY( char * Date8 ) | Returns numeric value of the day of the month for Date8. |
| DESCEND() | EXPN::DESCEND() | Descend - used to create descending indices |
| DTOC() | char * EXPN::DTOC( char * Date8 ) | Returns a date converted to format MM/DD/YY. |
| EXP() | xbDouble EXPN::EXP( xbDouble d ) | Returns exponential for supplied value. |
| IIF() | char * EXPN::IIF( xbShort, const char *,const char *) | If statement |
| INT() | xbLong EXPN::INT( xbDouble d ) | Converts any numeric value to an integer. |
| ISALPHA() | xbLong EXPN::ISALPHA( char * String ) | Returns TRUE if string is alpha. |
| ISLOWER() | xbLong EXPN::ISLOWER( char * String ) | Returns TRUE if string is lower case. |
| ISUPPER() | xbLong EXPN::ISUPPER( char * String ) | Returns TRUE if string is upper case. |
| LEFT() | char * EXPN::LEFT( char * String, xbShort Len ) | Returns Len characters from the left side of String. |
| LEN() | xbLong EXPN::LEN( char * String ) | eturns the number of characters in the String. |
| LOG() | xbDouble EXPN::LOG( xbDouble d ) | Returns the natural log of d. |
| LOWER() | char * EXPN::LOWER( char * String ) | Converts a string to lower case. |
| LTRIM() | char * EXPN::LTRIM( char * String ) | Eliminates leading white space from String. |
| MAX() | xbDouble EXPN::MAX( xbDouble d1, xbDouble d2 ) | Returns the larger of two numeric arguments. |
| MIN() | xbDouble EXPN::MIN(xbDouble d1, xbDouble d2 ) | Returns the smaller of two numeric arguments. |
| MONTH() | xbLong EXPN::MONTH( char * Date8 ) | Returns numeric month for Date8. |
| RECNO() | xbLong EXPN::RECNO() | Returns the current record number of the associated DBF file |
| REPLICATE() | char * EXPN::REPLICATE( char * String, xbShort Count ) | Replicates String Conut times. |
| RIGHT() | char * EXPN::RIGHT( char * String, xbShort Count ) | Returns Count characters from the right side of String. |
| RTRIM() | char * EXPN::RTRIM( char * String ) | Removes trailing white space from String. |
| SPACE() | char * EXPN::SPACE( xbShort Count ) | Returns a buffer filled with Count spaces. |
| SQRT() | xbDouble EXPN::SQRT( xbDouble d ) | Returns square root of d. |
| STR() |
char * EXPN::STR( xbDouble d ) char * EXPN::STR( xbDouble, xbShort ) char * EXPN::STR( xbDouble, xbShort, xbShort ) | Converts a number to a string. |
| SUBSTR() | char * EXPN::SUBSTR( char * String, xbShort StartPos, xbShort Len ) | Returns a string form String starting at position StartPos for a length of Len. |
| TRIM() | char * EXPN::TRIM( char * String ) | Same as RTRIM. |
| UPPER() | char * EXPN::UPPER( char * String ) | Converts a string to upper case. |
| VAL() | xbLong EXPN::VAL( char * String ) | Converts a string to an integer. |
| YEAR() | xbLong EXPN::YEAR( char * Date8 ) | Returns numeric year from Date8. |
| Method | Description |
|---|---|
| GetDoubleResult() | Get xbDouble result from processed expression |
| GetIntResult() | Get a xbLong result from processed expression |
| GetExpressionHandle() | Get an expression's handle |
| GetExpressionResultType(xbExpression *) | Get expression result type |
| GetStringResult() | Get xbString & result from processed expression |
| ParseExpression(char *,xbDbf *) | Parse an expression |
| ProcessExpression(xbExpression *) | Process a parsed expression |
| Return Code Value | Description |
|---|---|
| C | char * result from processed expression - use GetStringResult() |
| N | xbDouble result from processed expression - use GetDoubleResult() |
| L | xbLong (also logical) result from processed expression - use GetIntResult() |
