Octals and Hexadecimals

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Question: Is there a way to use octal and hexadecimal numbers in JavaScript?

Answer: Yes, in JavaScript you can use octals and hexadecimals.

The following are examples of octal numbers:

01234 
-077 
0312 

Positive octal numbers must begin with
0
(zero) followed by octal digit(s).
Negative octal numbers must begin with
-0
followed by octal digit(s).

And these are examples of hexadecimal numbers:

0xFF 
-0xCCFF 
0xabcdef 

Positive hexadecimals must begin with
0x
and negative hexadecimals must begin with
-0x
.

When you need to convert an octal or hexadecimal string to a number, use the function

parseInt(str,base)
. Consider these examples:
octalStr='377';
num = parseInt(octalStr,8);  // num now holds 255

hexStr='7F';
num = parseInt(hexStr,16);   // num now holds 127
The second argument of
parseInt
specifies the base of the number whose representation is contained in the original string. This argument can be any integer from 2 to 36.

See also:

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