Conversion of Dec to Hex in C# script - hex

Question

Trying to take a decimal value and convert it to hex. This is a C# script inside SCADA program. Following converts Hex to Dec just fine:
using System;
using MasterSCADA.Script.FB;
using MasterSCADA.Hlp;
using FB;
using System.Linq;
public partial class ФБ : ScriptBase
{
public override void Execute()
{
string hexValue = InVal;
int num = Int32.Parse(hexValue, System.Globalization.NumberStyles.HexNumber);
OutVal = num;
}
}
But I am having problem with the opposite - when I try to convert Dec to Hex. To my understanding the following should work but it gives an error: No overload for method 'ToString' takes '1' arguments in line 12
11 int? decValue = InVal;
12 string hexValue = decValue.ToString("X");
13 //string hexValue = string.Format("{0:F0}", decValue);
14 uint num = uint.Parse(hexValue, System.Globalization.NumberStyles.HexNumber);
15 OutVal = num;
I can avoid the error by using line 13 instead of 12 but in this case I am converting Hex to Dec instead of Dec to Hex. Can anyone help please?

Answer 1

You're trying to call ToString(string) on an int? value. Nullable<T> doesn't have a ToString(string) overload. You need something like:
string hexValue = decValue == null ? "" : decValue.Value.ToString("X");
(Obviously adjust the above depending on what you want the result to be if decValue is null.)

Answer 2

Try decValue.Value.ToString("X");
Your type is int? and not int

Answer 3

Here is my function:
using System;
using System.Collections.Generic;
class DecimalToHexadecimal
{
static string DecToHex(decimal decim)
{
string result = String.Empty;
decimal dec = decim;
while (dec >= 1)
{
var remainer = dec % 16;
dec /= 16;
result = ((int)remainer).ToString("X") + result;
}
return result;
}
static void Main()
{
Console.WriteLine("Enter decimal");
decimal dec = decimal.Parse(Console.ReadLine());
Console.WriteLine("Hexadecimal representation to {0} is {1}", dec, DecToHex(dec));
Console.ReadKey();
}
}