1. Chapter 2 Functions in Foxpro April 2003 cylau
Foxpro Chap. 2 Functions

2. Functions Used to evaluate data and return a result
can be assigned to a variable
x = LEN(‘I LOVE U’) // x =8
can be used directly in a print command
? LEN(‘I LOVE U’) // 8
input: parameter and argument //’I LOVE U’
output: return as a single value //8
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Foxpro Chap. 2 Functions

3. Commonly used functions
Character processing
Numeric processing
Date processing
Logical processing
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Foxpro Chap. 2 Functions

4. Functions for Character Processing(1)
LEN(‘ABC’) // 3
UPPER(‘Au’) // ‘AU’
LOWER(‘Au’) // ‘au’
PROPER(‘AU wan’) // ‘Au Wan’)
SPACE(3) // ‘ ’
LTRIM(‘ abc’) // ‘abc’
RTRIM(‘abc ’ ) // ‘abc’
ALLTRIM(‘ abc ’ ) // ‘abc’
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Foxpro Chap. 2 Functions

5. Functions for Character Processing(2)
LEFT(‘ABCDE’, 2) // ‘AB’
RIGHT(‘ABCDE’, 2) // ‘DE’
SUBSTR(‘ABCDE’, 2, 3) // ‘BCD’
STUFF(‘ABCDE’, 2, 3, ‘X’) // ‘AXE’
STUFF(‘ABCDE’, 2, 0, ‘X’) // ‘AXBCDE’)
STUFF(‘ABCDE’, 2, 3, ‘’) // ‘AE’
STUFF(‘ABCDE’, 7, 3, ‘X’) // ‘ABCDEX’
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Foxpro Chap. 2 Functions

6. Functions for Character Processing(3)
AT(‘CD’, ‘ABCDE’) // 3
AT(‘CE’, ‘ABCDE’) // 0
VAL(‘123’) // 123
‘123’ + ‘45’ // ‘12345’
VAL(‘123’) + VAL(‘45’) //
STR(123) // ‘123’
STR(123, 6, 2) // ‘123.00’
ASC(‘ABC’) // 65
CHR(65) // ‘A’
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Foxpro Chap. 2 Functions

7. Functions for Numeric Processing
ABS(-123) // 123
ROUND(123.45, 1) // 123.5
P.63 ROUND(numExp, numExp)
INT(456.78) // 456
CEILING(456.78) // 457
FLOOR(456.78) // 456
MOD(20, 7) // 6
SQRT(10) // 3.16
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Foxpro Chap. 2 Functions

8. Functions for Date Processing(1)
DATE() // today
DAY({04/23/2003}) // 23
DOW({04/23/2003}) // 4
note: 1st day of week is Sunday
CDOW({04/23/2003}) // Wednesday
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Foxpro Chap. 2 Functions

9. Functions for Date Processing(2)
MONTH({04/23/2003}) // 4
CMONTH({04/23/2003}) // April
YEAR({04/23/2003}) // 2003
YEAR({04/23/03}) // 1903
CTOD(‘01/23/00’) //{01/23/1900}
CTOD(‘01#23#00’) // { / / }
DTOC({01/23/00}) // ‘01/23/1900’
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Foxpro Chap. 2 Functions

10. Functions for Logical Processing
IIF(condition, exp1, exp2)
IIF(1=2, ‘abc’, ‘xyz’) // ‘xyz’
IIF(1=1, ‘abc’, ‘xyz’) // ‘abc’
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Foxpro Chap. 2 Functions

11. More on Functions What are the arguments in the function
STUFF(‘ABCDE’, 2, 3, ‘FG’)
What is the output?
What is the output of
SUBSTR(‘Amoy Garden’, address)
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Foxpro Chap. 2 Functions

12. Exercise
Do Ex. 1 to 15
on P and get a feel of the pitfalls that comes with some of the questions.
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Foxpro Chap. 2 Functions