Question

I’m working on converting a string into a hexadecimal and then perform & operation. Here is the scenario which seems to have an issue:

byte[] buffer;
string hexoutput;
char[] WaitXMSvalues = WaitXMS.ToCharArray(); // WaitXMS is a textbox, input = 10
foreach (char letter in WaitXMSvalues)
{
     // Get the integral value of the character. 
     int value = Convert.ToInt32(letter);

     // Convert the decimal value to a hexadecimal value in string form. 
     hexoutput = String.Format("{0:X}", value);
}            

buffer[0] = Convert.ToByte(hexoutput & 0xFF);

throws me an error at the above line:

Operator '&' cannot be applied to operands of type 'string' and 'int'

Whats the issue here?

I had done this in my C++ app as follows:

buffer[0] = WaitXMS->getText().getHexValue32() & 0xFF; 

and seems to work fine. Whats wrong with my C# code?

Please help!

Answer 1

hexoutput is a string; there is no defined & operation between string and an integer – did you typo in the question? If you are trying to apply a byte-mask, you’ll have to do that when the value is some kind of integer/byte; not as a string.

For example, the following would work, but would be somewhat pointless:

buffer[0] = (byte) (Convert.ToByte(hexoutput, 16) & 0xFF);

There’s also a significant error in that your hexoutput variable is defined inside the loop, but accessed outside, again suggesting that the code being shown is not the actual code – that would have the compiler error:

The name ‘hexoutput’ does not exist in the current context