Converting integer value to bits and storing it into a char array?

I am designing a Reliable data transmission over UDP, where in the UDP data buffer which is a character array and in my first 2 bytes of it I ha开发者_如何转开发ve to put bits like 00010000.... and so on and I want to know how to achieve this. Please let me know if you need any info, thanks in advance for your help, I really appreciate it

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write a function of converting a numbers into an string ( character array ) steps : 1.divide a integer number by 2 and store the modulus value in a character array. 2.subtract the quotient value with an integer and store the result in the same integer 3. keep on doing the step 1 and 2 until the integer value becomes zero.

Hope that this would be the simple conversion program

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Are you asking, "How to convert an [u]int-stream into a byte-string?"

Then you can try this:

1. Pick next integer x = uint[i]
2. Get four bytes out of it as
 b4 = x & 0xFF000000
 b3 = x & 0x00FF0000
 b2 = x & 0x0000FF00
 b1 = x & 0x000000FF
3. Write the four bytes into the stream s, e.g.
 s << b4 << b3 << b2 << b1;
4. i += 1
5. Go to 1

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or use more generic function to write a single bit into buffer (char array) `

void setBitAt( char* buf, int bufByteSize, int bitPosition, bool value )
{
    if(bitPosition < sizeof(char)*8*bufByteSize)
    {
        int byteOffset= bitPosition/8;
        int bitOffset = bitPosition - byteOffset*8;

        if(value == true)
        {
             buf[byteOffset] |=  (1 << bitOffset);
        }
        else
        {
             buf[byteOffset] &= ~(1 << bitOffset);;
        }
    }
}

`