- Data Structure
- Networking
- RDBMS
- Operating System
- Java
- MS Excel
- iOS
- HTML
- CSS
- Android
- Python
- C Programming
- C++
- C#
- MongoDB
- MySQL
- Javascript
- PHP
- Physics
- Chemistry
- Biology
- Mathematics
- English
- Economics
- Psychology
- Social Studies
- Fashion Studies
- Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
unpack() function in PHP
The unpack() function unpacks data from a binary string.
Syntax
unpack(format, data)
Parameters
format − The format to use. Here are the possible values
a −NUL-padded string
A − SPACE-padded string
h − Hex string, low nibble first
H − Hex string, high nibble first
c − signed char
C −unsigned char
s − signed short (always 16 bit, machine byte order)
S − unsigned short (always 16 bit, machine byte order)
n − unsigned short (always 16 bit, big endian byte order)
v − unsigned short (always 16 bit, little endian byte order)
i − signed integer (machine dependent size and byte order)
I − unsigned integer (machine dependent size and byte order)
l − signed long (always 32 bit, machine byte order)
L − unsigned long (always 32 bit, machine byte order)
N − unsigned long (always 32 bit, big endian byte order)
V − unsigned long (always 32 bit, little endian byte order)
f − float (machine dependent size and representation)
d − double (machine dependent size and representation)
x − NUL byte
X − Back up one byte
Z − NUL-padded string
@ − NUL-fill to absolute position
data − The binary data to be packed.
Return
The unpack() function returns an array on success, or false on failure.
Example
<?php $var = "Jacob"; print_r(unpack("C*myint",$var)); ?>
Output
The following is the output.
Array ( [myint1] => 74 [myint2] => 97 [myint3] => 99 [myint4] => 111 [myint5] => 98 )