Core Function Unpack

Revision as of 12:45, 17 November 2011 (view source) UberFoX (Talk | contribs) (→Remarks) ← Older edit		Revision as of 12:46, 17 November 2011 (view source) UberFoX (Talk | contribs) (→Example) Newer edit →
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	=== Example ===		=== Example ===
−	Convert a string into a binary array and back again:	+	Go see [[Core Function Pack|Pack( <expression>, <expressions> )]] for a list of formats and examples.
−		+
−	<syntaxhighlight lang="sputnik">	+
−	$arr = Pack("z0", "Hello World!")	+
−	For $i In $arr	+
−	println($i)	+
−	Next	+
−	$str = Unpack("z0", $arr)	+
−	println($str)	+
−	</syntaxhighlight>	+
−		+
−	Convert a dobule into a binary array and back again:	+
−	<syntaxhighlight lang="sputnik">	+
−	$arr = Pack("d", 777.42)	+
−	For $i In $arr	+
−	println($i)	+
−	Next	+
−	$str = Unpack("d", $arr)	+
−	println($str)	+
−	</syntaxhighlight>	+
−		+
−	Convert a int into a binary array and back again:	+
−	<syntaxhighlight lang="sputnik">	+
−	$arr = Pack("d", (int)777)	+
−	For $i In $arr	+
−	println($i)	+
−	Next	+
−	$str = Unpack("d", $arr)	+
−	println($str)	+
−	</syntaxhighlight>	+
−		+
−	Convert a string into a hex and back again:	+
−	<syntaxhighlight lang="sputnik">	+
−	$hex = Join(Unpack("*H", Pack("z0", "Hello World!")), '')	+
−	println("Hex String: " . $hex)	+
−	$str = Unpack("z0", Pack("h", $hex))	+
−	println("Normal String: " . $str)	+
−	</syntaxhighlight>	+
−		+
−	To pack two integers in big endian format, you would use this:	+
−	<syntaxhighlight lang="sputnik">	+
−	$bytes = Pack ("^ii", 1234, 4542);	+
−	</syntaxhighlight>	+
−		+
−	More Examples:	+
−	<syntaxhighlight lang="sputnik">	+
−	; The following means:	+
−	; Little endian encoding of a Int16, followed by an aligned	+
−	; int32 value.	+
−	$r = Pack("_s!i", 0x7b, 0x12345678);	+
−	For $i In $r	+
−	print(Hex($i) . " ")	+
−	Next	+
−	; Prints 7B 0 0 0 80 56 34 12	+
−		+
−	$bytes = Pack("CCCC", 65, 66, 67, 68)	+
−	println($bytes) ; Prints 4-byte sequence for "ABCD"	+
−		+
−	$bytes = Pack("4C", 65, 66, 67, 68)	+
−	println($bytes) ; Prints 4-byte sequence for "ABCD"	+
−		+
−	$bytes = Pack("*C", 65, 66, 67, 68)	+
−	println($bytes) ; Prints 4-byte sequence for "ABCD"	+
−		+
−	$bytes = Pack("^ii", 0x1234abcd, 0x7fadb007)	+
−	For $i In $bytes	+
−	print(Hex($i) . " ")	+
−	Next	+
−	println("") ; Result: 12 34 ab cd 7f ad b0 07	+
−		+
−	; Encode 3 integers as big-endian, but only provides two as arguments,	+
−	; this defaults to zero for the last value.	+
−	$bytes = Pack("^iii", 0x1234abcd, 0x7fadb007)	+
−	For $i In $bytes	+
−	print(Hex($i) . " ")	+
−	Next	+
−	println("") ; Result: 12 34 ab cd 7f ad b0 07 00 00 00 00	+
−		+
−	; Encode as little endian, pack 1 short, align, 1 int	+
−	$bytes = Pack("_s!i", 0x7b, 0x12345678);	+
−	For $i In $bytes	+
−	print(Hex($i) . " ")	+
−	Next	+
−	println("") ; Result: 7b 00 00 00 78 56 34 12	+
−		+
−	; Encode a string in utf-8 with a null terminator	+
−	$bytes = Pack("z8", "hello")	+
−	For $i In $bytes	+
−	print(Hex($i) . " ")	+
−	Next	+
−	println("") ; Result: 68 65 6c 6c 6f 00 00 00 00	+
−		+
−	; Little endian encoding, for Int16, followed by an aligned	+
−	; Int32	+
−	$bytes = Pack("_s!i", 0x7b, 0x12345678)	+
−	For $i In $bytes	+
−	print(Hex($i) . " ")	+
−	Next	+
−	println("") ; Result: 7b 00 00 00 78 56 34 12	+
−	</syntaxhighlight>	+
	[[Category:Core Function]]		[[Category:Core Function]]

---

Revision as of 12:46, 17 November 2011

Unpack( <expression>, <binary-array/string>, <flag> )

Contents 1 Description 1.1 expression 1.2 binary-array/string 1.3 flag 2 Return Value 3 Remarks 4 Example

Description

Unpack data from a binary array

expression

The format string to use.

binary-array/string

An binary array of bytes such as one produced by the Pack function.

OR

A string to be converted into a binary array of bytes (z0 ASCII encoding).

flag

Optional; Control what is returned options are:

0 = Return an array

1 = Return a string

Return Value

Success: Returns the array of data (Even if its only 1 item) unless the flag is set to 1 then it will return a string.

Failure: Returns empty array.

Remarks

Go see Pack( <expression>, <expressions> ) for a list of formats and examples.

Example

Go see Pack( <expression>, <expressions> ) for a list of formats and examples.