Input and output in foxpro
As we already know that data can be entered into tables through the APPEND/BROWSE commands. Data entry for tables can also be done through programs. There arises a need to display and accept information in a formatted way.
The @…say command is used to place data at a particular screen location and to display data stored in fields or memory variables. The @…get commands is used to retrieve data.
Displaying data
@…say command: -
Syntax: -
@<Row, columns>SAY<expr>
[Function<exprC1>]
[Picture<expr2>]
[size<exprn],<exprn2>]
[font<exprC3>[,<exprN3]]
[STYLE, exprC4>]
Example:-
@2, 10 say “hello welcome to FoxPro”
Syntax:
Input
@row,column | say <char_exp> get <mem_var>
Output
@row ,column | say <char_exp> get <mem_var>
Clear
@row, column to row, column clear
Clear all
Ex
@5, 5 clear to 20, 20
Box Command
@row1, column1 to row2, column 2
Picture clause
PICTURE clause is used to control of display or the information to be accepted.
@..SAY...GETS PICTURE CODES:
A - Allows only alphabets
9 - Allows only digits, signs for numeric data
N - Allows Letters and Digits
# - Allows Only Digits, Blanks and Signs
X - Allows any Character
L - Allows any Logical Data T, t, F, f, Y, y, N, n
Y - Allows Only Y, y, N, n
! - Converts letters into uppercase.
* - Displays asterisk in place of leading zeros.
, - Display the comma
. - Display the decimal Point.
Function Clause
You can include the function clause, the picture clause or both to control how<expr> is displayed or printed. A function clause affects the entire expression. It contains only the following function code.
Function code & Purpose
B Left – justifies numeric data within the display region.
Example:
Clear
Store 2750 to num
@5,20 say num
@6,20 say num function “B”
C Cr is displayed after a positive number to indicate a credit. Can be used with numeric data only.
Example:-
Clear
Store 15432.00 to amt
@5,20 say amt
@6,20 say amt function “c”
D Uses the current set DATE format.
Example:-
Clear
Store 230801 to num
Store “foxproprograming” to tit
@5,20 say num function “D”
@6,20 say tit function “D”
E Edits date type data as British date
Example:-
Clear
Store 230904 to num
@6,20 say num function “E”
T Trim leading and trailing blanks from<expr>
Example:-
Clear
@5,20 ”fox” to tit
@6,20 say tit function “T”
X DB is displayed after negative numbers to indicate a debit. used only with numberic data.
Example:-
Clear
Store -15432.00 to amt
@5,20 say amt
@6,20 say amt function “X”
Z <expr> is displayed as all blanks if its numeric
value is 0. used only with numeric data.
Example:
Clear
Store o to amt
@5,20 say amt
@6,20 say amt function “z”
( Encloses negative numbers in parentheses. Used only with numeric data.
Example:-
Clear
Store –755 to amt
@5,20 say amt
@6,20 say amt function “(“
! Converts alphabetic characters to upper-case used with character data-only
Example:-
Clear
Store “foxpro programming” to tit
@6,20 say tit function “!”
^ Displays numeric data using scientific notation. Used with numeric data only.
Example:-
Clear
Store 75815 to amt
@6,20 say amt function “^”
$
Displays data in currently format. the currency symbol appears before or after the field value depending on the current setting of set currency. used with numeric data only.
Example:-
Clear
Store 75815 to amt
@6,20 say amt function “$”
Picture expression can include the following characters:-
X Allows any character.
Y Allows logical Y, y, N and n only. Converts y and n to Y and N, respectively.
! Displays the current currency symbol specified by set currency. By default, the symbol is placed immediately before or after the field.
* Asterisks are displayed in front of the numeric value. Use with a dollar sign $ for check protection.
. A decimal point specifies the decimal point position.
, A comma is used to specifies digits to the left of the decimal point.
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