C# Number to BitMask32 to Values

Question

I am getting a number such as 513. I need to convert this number to a bitmask32 then I need to count where each 1 bit is in the array

For Example 513 = 0 and 9

How would I go about converting the number to a bit32 then reading the values?

Right now I am just converting the number to a string binary value:

string bit = Convert.ToString(513, 2);

Would there be a more effective way to do this? How would I convert the value to a bit array?

Thanks

Answer 1

var val = 513;
for(var pos=0;;pos++)
{
    var x = 1 << pos;
    if(x > val) break;
    if((val & x) == x)
    {
        Console.WriteLine(pos);
    }
}

Answer 2

BitVector32类是一个实用程序类，如果你真的想要保留位图，可以帮助你解决这个问题。

Answer 3

using System.Collections;

int originalInt = 7;
byte[] bytes = BitConverter.GetBytes(originalInt);
BitArray bits = new BitArray(bytes);
int ndx = 9; //or whatever ndx you actually care about

if (bits[ndx] == true)
{
     Console.WriteLine("Bit at index {0} is on!", ndx);
}

Answer 4

要测试数字n位#i：

if ((n & (1 << i)) != 0)