Cover by Steven Levithan, Jan Goyvaerts

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6.2. Hexadecimal Numbers

Problem

You want to find hexadecimal numbers in a larger body of text, or check whether a string variable holds a hexadecimal number.

Solution

Find any hexadecimal number in a larger body of text:

\b[0-9A-F]+\b
Regex options: Case insensitive
Regex flavors: .NET, Java, JavaScript, PCRE, Perl, Python, Ruby
\b[0-9A-Fa-f]+\b
Regex options: None
Regex flavors: .NET, Java, JavaScript, PCRE, Perl, Python, Ruby

Check whether a text string holds just a hexadecimal number:

\A[0-9A-F]+\Z
Regex options: Case insensitive
Regex flavors: .NET, Java, PCRE, Perl, Python, Ruby
^[0-9A-F]+$
Regex options: Case insensitive
Regex flavors: .NET, Java, JavaScript, PCRE, Perl, Python

Find a hexadecimal number with a 0x prefix:

\b0x[0-9A-F]+\b
Regex options: Case insensitive
Regex flavors: .NET, Java, JavaScript, PCRE, Perl, Python, Ruby

Find a hexadecimal number with an &H prefix:

&H[0-9A-F]+\b
Regex options: Case insensitive
Regex flavors: .NET, Java, JavaScript, PCRE, Perl, Python, Ruby

Find a hexadecimal number with an H suffix:

\b[0-9A-F]+H\b
Regex options: Case insensitive
Regex flavors: .NET, Java, JavaScript, PCRE, Perl, Python, Ruby

Find a hexadecimal byte value or 8-bit number:

\b[0-9A-F]{2}\b
Regex options: Case insensitive
Regex flavors: .NET, Java, JavaScript, PCRE, Perl, Python, Ruby

Find a hexadecimal word value or 16-bit number:

\b[0-9A-F]{4}\b
Regex options: Case insensitive
Regex flavors: .NET, Java, JavaScript, PCRE, Perl, Python, Ruby

Find a hexadecimal double word value or 32-bit number:

\b[0-9A-F]{8}\b ...

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