Question

I need to convert an integer number to the hex value. It will look like this:

0x0201cb77192c851c

When I do

string hex = int.ToString("x")

in C#, it returns

201cb77192c851c

How can I get the required result?

Answer 1

One way would be to append the number of digits you need, after “x”. This will pad the output with leading zeros as necessary.

"0x" + myLong.ToString("x16");

or

string.Format("0x{0:x16}", myLong);

From The Hexadecimal (“X”) Format Specifier
:

The precision specifier indicates the
minimum number of digits desired in
the resulting string. If required, the
number is padded with zeros to its
left to produce the number of digits
given by the precision specifier.