Keyboard input/Obtain a Y or N response: Difference between revisions
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Obtain a valid Y or N response from the keyboard. The keyboard should be flushed, so that any outstanding keypresses are removed, preventing any exiting Y or N keypress from being evaluated. The response should be obtained as soon as Y or N are pressed, and there should be no need to press an enter key. |
Obtain a valid Y or N response from the [[input device::keyboard]]. The keyboard should be flushed, so that any outstanding keypresses are removed, preventing any exiting Y or N keypress from being evaluated. The response should be obtained as soon as Y or N are pressed, and there should be no need to press an enter key. |
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[[user input::task]] |
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=={{header|BASIC}}== |
=={{header|BASIC}}== |
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Revision as of 01:45, 19 October 2010
You are encouraged to solve this task according to the task description, using any language you may know.
Obtain a valid Y or N response from the keyboard. The keyboard should be flushed, so that any outstanding keypresses are removed, preventing any exiting Y or N keypress from being evaluated. The response should be obtained as soon as Y or N are pressed, and there should be no need to press an enter key. task
BASIC
ZX Spectrum Basic
10 IF INKEY$<>"" THEN GOTO 10 20 PRINT "Press Y or N to continue" 30 LET k$ = INKEY$ 40 IF k$ = "y" OR k$ = "Y" OR k$ = "n" OR k$ = "N" THEN GOTO 60 50 GOTO 30 60 PRINT "The response was "; k$
PureBasic
Inkey() returns the character string of the key which is being pressed at the time. <lang PureBasic>PrintN("Press Y or N to continue")
Repeat
; Get the key being pressed, or a empty string. Key$=UCase(Inkey()) ; ; To Reduce the problems with an active loop ; a Delay(1) will release the CPU for the rest ; of this quanta if no key where pressed. Delay(1)
Until Key$="Y" Or Key$="N" PrintN("The response was "+Key$)</lang>
Tcl
<lang tcl>proc yesno Template:Message "Press Y or N to continue" {
fconfigure stdin -blocking 0
exec stty raw
read stdin ; # flush
puts -nonewline "${message}: "
flush stdout
while {![eof stdin]} {
set c [string tolower [read stdin 1]]
if {$c eq "y" || $c eq "n"} break
}
puts [string toupper $c]
exec stty -raw
fconfigure stdin -blocking 1
return [expr {$c eq "y"}]
}
set yn [yesno "Do you like programming (Y/N)"]</lang>