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The INPUT$ function is used to receive data from the user's keyboard, an open file or an open port.


result$ = INPUT$(numberOfBytes%[, fileOrPortNumber])

  • Keyboard input is limited to the INTEGER numberOfBytes% (characters) designated by program.
  • The keyboard is the default device when a file or port number is omitted. The 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$(8) character being added to an entry.
  • Use LOCATE , , 1 to view the cursor entry. Turn the cursor off using LOCATE , , 0.
  • Use _DEST _CONSOLE before INPUT$ is used to receive input from a console window.


  • 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.


Example 1: A keyboard limited length entry can be made with a fixed blinking cursor. Entry must be completed before it can be shown.

LOCATE 10, 10, 1 'display fixed cursor at location year$ = INPUT$(4) 'waits until all 4 digits are entered PRINT year$ 'display the text entry

Example 2: Reading bytes from a text file for an 80 wide screen mode.

LOCATE 5, 5, 1 'locate and display cursor OPEN "Diary.txt" FOR INPUT AS #1 'open existing text file text$ = INPUT$(70, 1) LOCATE 5, 6, 0: PRINT text$ 'print text and turn cursor off

Example 3: Getting the entire text file data as one string value.

OPEN "Diary.txt FOR BINARY AS #1 'open an existing file up to 32767 bytes IF LOF(1) <= 32767 THEN Text$ = INPUT$(LOF(1), 1) CLOSE #1

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).

See also

Keyword Reference - Alphabetical
Keyword Reference - By Usage
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