mirror of
https://github.com/QB64Official/qb64.git
synced 2024-08-22 05:35:08 +00:00
58 lines
3 KiB
Text
58 lines
3 KiB
Text
The [[INPUT$]] function is used to receive data from the user's keyboard, an open file or an open port.
|
|
|
|
|
|
{{PageSyntax}}
|
|
: {{Parameter|result$}} = [[INPUT$]]({{Parameter|numberOfBytes%}}[, fileOrPortNumber])
|
|
|
|
|
|
* Keyboard input is limited to the [[INTEGER]] {{Parameter|numberOfBytes%}} (characters) designated by program.
|
|
* The keyboard is the default device when a file or port number is omitted. The {{Parameter|numberOfBytes%}} is number of key presses to read.
|
|
* INPUT$ will wait until the number of bytes are read from the keyboard or port. One byte per loop is recommended with ports.
|
|
* [[RANDOM]] opened file bytes can be up to the [[LEN]] = recordLength statement, or 128 if no statement is used.
|
|
* fileOrPortNumber is the number that was used in the [[OPEN]] AS statement.
|
|
* Returns [[STRING]] values including spaces or even extended [[ASCII]] characters.
|
|
* Backspace key results in the [[CHR$]](8) character being added to an entry.
|
|
* Use {{InlineCode}}[[LOCATE]] , , 1{{InlineCodeEnd}} to view the cursor entry. Turn the cursor off using {{InlineCode}}LOCATE , , 0{{InlineCodeEnd}}.
|
|
* Use [[_DEST]] [[_CONSOLE]] before INPUT$ is used to receive input from a [[$CONSOLE|console]] window.
|
|
|
|
|
|
{{PageQBasic}}
|
|
* {{Parameter|numberOfBytes%}} could not exceed 32767 in [[BINARY]] files or a QBasic error would occur.
|
|
* Ctrl + Break would not interrupt the QBasic program until there was a full INPUT$ key entry. In '''QB64''' Ctrl + Break will immediately exit a running program.
|
|
|
|
|
|
{{PageExamples}}
|
|
''Example 1:'' A keyboard limited length entry can be made with a fixed blinking cursor. Entry must be completed before it can be shown.
|
|
{{CodeStart}} '' ''
|
|
{{Cl|LOCATE}} 10, 10, 1 'display fixed cursor at location
|
|
year$ = {{Cl|INPUT$}}(4) 'waits until all 4 digits are entered
|
|
PRINT year$ 'display the text entry '' ''
|
|
{{CodeEnd}}
|
|
|
|
|
|
''Example 2:'' Reading bytes from a text file for an 80 wide screen mode.
|
|
{{CodeStart}} '' ''
|
|
{{Cl|LOCATE}} 5, 5, 1 'locate and display cursor
|
|
{{Cl|OPEN}} "Diary.txt" FOR {{Cl|INPUT (file mode)|INPUT}} AS #1 'open existing text file
|
|
text$ = {{Cl|INPUT$}}(70, 1)
|
|
{{Cl|LOCATE}} 5, 6, 0: PRINT text$ 'print text and turn cursor off '' ''
|
|
{{CodeEnd}}
|
|
|
|
|
|
''Example 3:'' Getting the entire text file data as one string value.
|
|
{{CodeStart}} '' ''
|
|
{{Cl|OPEN}} "Diary.txt FOR {{Cl|BINARY}} AS #1 'open an existing file up to 32767 bytes
|
|
IF {{Cl|LOF}}(1) <= 32767 THEN Text$ = {{Cl|INPUT$}}(LOF(1), 1)
|
|
{{Cl|CLOSE}} #1 '' ''
|
|
{{CodeEnd}}
|
|
:''Explanation:'' The IF statement gets the entire contents when the file size is less than 32768. The program can then work with the string by using [[MID$]] or [[INSTR]]. Note: A text file string will also have '''CrLf''' line break end characters [[CHR$]](13) + [[CHR$]](10).
|
|
|
|
|
|
{{PageSeeAlso}}
|
|
* [[INPUT]], [[LINE INPUT]] {{text|(keyboard input)}}
|
|
* [[INPUT (file mode)]], [[INPUT (file statement)|INPUT #]], [[LINE INPUT (file statement)|LINE INPUT #]] {{text|(file input)}}
|
|
* [[OPEN]], [[LOC]] {{text|(file)}}
|
|
* [[LOCATE]] {{text|(cursor on/off)}}
|
|
|
|
|
|
{{PageNavigation}}
|