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65 lines
1.5 KiB
Markdown
65 lines
1.5 KiB
Markdown
The [_READBIT](_READBIT) function is used to check the state of a specified bit of a integer value.
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## Syntax
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> result = [_READBIT](_READBIT)(numericalVariable, numericalValue)
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## Parameter(s)
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* numericalVariable is the variable to read the state of a bit of and can be of the following types: [_BYTE](_BYTE), [INTEGER](INTEGER), [LONG](LONG), or [_INTEGER64](_INTEGER64).
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* Integer values can be signed or [_UNSIGNED](_UNSIGNED).
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* numericalValue the number of the bit to be read.
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## Description
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* Used to check the current state of a bit in an integer value.
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* Returns -1 if the bit is set(1), otherwise returns 0 if the bit is not set(0)
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* Bits start at 0 (so a [_BYTE](_BYTE) has bits 0 to 7, [INTEGER](INTEGER) 0 to 15, and so on)
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## Availability
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* Version 1.4 and up.
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## Example(s)
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```vb
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A~%% = _SETBIT(A~%%,4)
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PRINT "Bit 4 is currently ";
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IF _READBIT(A~%%,4) = -1 THEN PRINT "ON" ELSE PRINT "OFF"
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PRINT "And bit 2 is currently ";
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IF _READBIT(A~%%,2) = -1 THEN PRINT "ON" ELSE PRINT "OFF"
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```
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```text
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Bit 4 is currently ON
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And bit 2 is currently OFF
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```
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```vb
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B& = 12589575
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PRINT "B& ="; B&
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FOR I%% = 31 TO 0 STEP -1 '32 bits for a LONG value
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Binary$ = Binary$ + LTRIM$(STR$(ABS(_READBIT(B&, I%%))))
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NEXT I%%
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PRINT "B& in binary is: "; Binary$
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```
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```text
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B& = 12589575
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B& in binary is: 00000000110000000001101000000111
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```
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## See Also
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* [_SHL](_SHL), [_SHR](_SHR), [INTEGER](INTEGER), [LONG](LONG)
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* [_SETBIT](_SETBIT), [_BYTE](_BYTE), [_INTEGER64](_INTEGER64)
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* [_RESETBIT](_RESETBIT), [_TOGGLEBIT](_TOGGLEBIT)
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