Convert an integer to a binary string with leading zeros

Question

I need to convert int to bin and with extra bits.

string aaa = Convert.ToString(3, 2); 

it returns 11, but I need 0011, or 00000011.

How is it done?

Answer 1

11 is binary representation of 3. The binary representation of this value is 2 bits.

3 = 2⁰ * 1 + 2¹ * 1

You can use String.PadLeft(Int, Char) method to add these zeros.

// convert number 3 to binary string.  // And pad '0' to the left until string will be not less then 4 characters Convert.ToString(3, 2).PadLeft(4, '0') // 0011 Convert.ToString(3, 2).PadLeft(8, '0') // 00000011