How can I convert/cast an integer value to a byte value in C# but do not wrap around or throw an exception? What I'm looking for is some sort of bool byte.TryConvert(int i, out b) method.
I tried Convert.ToByte and direct casts.
byte b = Convert.ToByte(257); // throws OverflowException
byte b = (byte)257; // results in 1
byte b = (byte)(-1); // results in 255
Or do I have to "reverse-cast" (for lack of a better word) the byte to an int and compare it to the original value?
In my concrete use case I have in fact a nullable byte type. ... is there such a method as bool byte.TryConvert(int i, out b)?
No. You would have to do something like:
byte? result = (value >= byte.MinValue && value <= byte.MaxValue)
? (byte)value : (byte?)null;
? (byte?)value : null and ? (byte)value : (byte?)null? I know that .NET sometimes generates weird (iow inefficient) IL code when nullable primitive types are involved.byte?Write the method yourself. Check the value of the int. If it is in range, return true and assign it to the out parameter with a direct cast. If not, return false, setting the out parameter to zero.
Downvoter please comment.
EDIT here's my solution; unlike Marc Gravell's, it does not introduce nullability:
public bool TryToByte(int value, out byte result)
{
var success = value >= byte.MinValue && value <= byte.MaxValue;
result = (byte)(success ? value : 0);
return success;
}
If you don't want the int to "overflow" to another value but stays in the range of a Byte, e.g. if < 0 then results 0, and if > 255 then results 255, else stays the same. Just add a Clamp before converting.
(byte)Mathf.Clamp(yourIntValue, 0, byte.MaxValue)
You can use this to other types of course. If you're sure the min value of the type, then you can change 0 to the type's MinValue. For example:
(sbyte)Mathf.Clamp(yourIntValue, sbyte.MinValue, sbyte.MaxValue)
null(for my usecase). A method which returns true if casting/conversion was successful and false for failed conversions would be best (if such a function already exists in the .NET framework).nullis not a valid value forbyte, so you can't do that; you'd need to usebyte?or similar