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The _READBIT function is used to check the state of a specified bit of a integer value.


result = _READBIT(numericalVariable, numericalValue)


  • numericalVariable is the variable to read the state of a bit of and can be of the following types: _BYTE, INTEGER, LONG, or _INTEGER64.
  • Integer values can be signed or _UNSIGNED.
  • numericalValue the number of the bit to be read.


  • Used to check the current state of a bit in an integer value.
  • Returns -1 if the bit is set(1), otherwise returns 0 if the bit is not set(0)
  • Bits start at 0 (so a _BYTE has bits 0 to 7, INTEGER 0 to 15, and so on)


  • Version 1.4 and up.


Example 1:

A~%% = _SETBIT(A~%%,4) PRINT "Bit 4 is currently "; IF _READBIT(A~%%,4) = -1 THEN PRINT "ON" ELSE PRINT "OFF" PRINT "And bit 2 is currently "; IF _READBIT(A~%%,2) = -1 THEN PRINT "ON" ELSE PRINT "OFF"

Bit 4 is currently ON And bit 2 is currently OFF

Example 2:

B& = 12589575 PRINT "B& ="; B& FOR I%% = 31 TO 0 STEP -1 '32 bits for a LONG value Binary$ = Binary$ + LTRIM$(STR$(ABS(_READBIT(B&, I%%)))) NEXT I%% PRINT "B& in binary is: "; Binary$

B& = 12589575 B& in binary is: 00000000110000000001101000000111

See also

Keyword Reference - Alphabetical
Keyword Reference - By Usage
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