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parseInt('bcedfg',16)

Base on this code I am getting 773855 in a JavaScript,

I go through the conversion table , and not sure how to get this "773855" value

my question is how parseint e out with this "773855" value , because I wanted to translate this tiny code in to a c# code , and is that any similar way in c# allow me to get this "773855" value

parseInt('bcedfg',16)

Base on this code I am getting 773855 in a JavaScript,

I go through the conversion table , and not sure how to get this "773855" value

my question is how parseint e out with this "773855" value , because I wanted to translate this tiny code in to a c# code , and is that any similar way in c# allow me to get this "773855" value

• c#
• javascript

Share Improve this question Follow edited Oct 21, 2012 at 9:55 gdoron 150k5959 gold badges302302 silver badges371371 bronze badges asked Oct 21, 2012 at 9:47 abc cbaabc cba 2,6331111 gold badges3232 silver badges5050 bronze badges 1

• The problem here is the "bcedfg" is be interpreted as hex(base: 16). Yet the hex scale rolls over at "f". – SReject Commented Oct 21, 2012 at 9:50

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2 Answers 2

Sorted by: Reset to default 10

The bcedfg is being interpreted as hex(base: 16). Yet the hex scale rolls over after f so, in javascript, the g and everything after it is being removed before converting. With that said, here's how the conversion works:

decValueOfCharPosition = decValueOfChar * base ^ posFromTheRight

so:

b = 11 * 16^4 = 11 * 65536 = 720896
c = 12 * 16^3 = 12 * 4096 = 49152
d = 13 * 16^2 = 13 * 256 = 3328
e = 14 * 16^1 = 14 * 16 = 224
f = 15 * 16^0 = 15 * 1 = 15

Once you know the decimal value for each character's position, just add them together to get the converted decimal value:

b(720896) + c(49152) + d(3328) + e(224) + f(15) = 773855

C and it's offspring are not so lenient when it es to the input. Instead of removing the first invalid character and any characters that may follow after, C throws a Format Exception. To work around this to get the javascript functionality you must first remove the invalid character and it's followings, then you can use:

Convert.ToInt32(input, base)

I didn't include a way to remove invalid characters due to there being multiple ways of doing as such and my subpar knowledge of C

Use Convert.ToInt32:

Convert.ToInt32(theString, 16)

It uses this overload:

public static int ToInt32(string value, int fromBase)

Note that you will get FormatException because of the g in the string:

FormatException
value contains a character that is not a valid digit in the base specified by fromBase. The exception message indicates that there are no digits to convert if the first character in value is invalid; otherwise, the message indicates that value contains invalid trailing characters.

MSDN

You're not getting error in javascript as js tends to "forgive" too much errors, this one one of those examples.

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