Converting a boolean array into a hexadecimal number

Question

Is there an easy way to convert an array of boolean values into 8-bit hexadecimal equivlents? For example, if I have

 bool[] BoolArray = new bool[] { true,false,true,true,false,false,false,true };

If true values=1 and false values=0 then I'd like a method or function that would convert the above array to 0xB1 (10110001).

Does there exist such a function or method to do this? I am using C#, by the way.

score 10 · Accepted Answer · answered Apr 04 '11 at 00:42

10

Yes, you can use the BitArray class. Something like this should do it:

BitArray arr = new BitArray(BoolArray);
byte[] data = new byte[1];
arr.CopyTo(data, 0);

If by "8-bit hexadecimal" you mean the string representation, you can use the BitConverter class for that:

string hex = BitConverter.ToString(data);

answered Apr 04 '11 at 00:42

Guffa

687,336
108
737
1,005

This worked, but I forgot to answer it till now! Thanks for the help! – Icemanind May 08 '11 at 15:42

v.oddou · Answer 2 · 2021-07-29T05:17:43.913

2

How about

static int BoolArrayToInt(bool[] arr)
{
    if (arr.Length > 31)
        throw new ApplicationException("too many elements to be converted to a single int");
    int val = 0;
    for (int i = 0; i < arr.Length; ++i)
        if (arr[i]) val |= 1 << i;
    return val;
}

static string ToHexStr(int i) { return i.ToString("X8"); }

note: an editor remarked that arr[0] is the LSB but he expected MSB. This is an API consideration, if you prefer your LSB to be at arr[length-1] just reverse the array before passing to that function.

edited Jul 29 '21 at 05:17

answered Apr 20 '16 at 06:30

v.oddou

6,476
3
32
63

Best answer, which allows non 8bit encodings. – Soleil Oct 29 '20 at 03:03

score -1 · Answer 3 · edited Nov 29 '19 at 01:16

The Binary part can be achieved through this method:

bool[] boolArray = {true, false, true} will give 101:

int BoolArrayToInt(bool[] bArray)
{

    char[] caseChar = new char[bArray.Length];

    for(int i = 0; i < bArray.Length; i++)
    {
        if (bArray[i] == true)
        {
            caseChar[i] = '1';
        }
        else
        {
            caseChar[i] = '0';
        }
    }

    string caseString = new string(caseChar);
    int caseNum = System.Convert.ToInt32(caseString);
    return caseNum;

}

Converting a boolean array into a hexadecimal number

3 Answers3

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