I have a byte array represented by hex values, these are time durations. The data could be converted to integer values and multiplied by a constant to get the timings. The decoding of the data will be saved to a file as a series of hex strings. What would be an efficient way of manipulating hex values?
I was looking at performance issues when dealing with data formats, as I have to work with more than one format at different stages (calculations, data display, etc.). Most examples show the conversion from byte[] to hex string ("1A 3C D4"), and viceversa, but I was looking for an alternative, which is to convert to Int16 and use char[] array.
You don't have a byte array representing hex values. You have a byte array representing numbers. The base you represent a number in is only relevant when you're representing it.
To put it a different way: if you thought of your byte array as representing decimal integers instead, how do you imagine it would be different? Is my height different if I represent it in feet and inches instead of metres?
Now, if you're trying to represent 16-bit numbers, I'd suggest that using a byte array is a bad idea. Use a ushort[] or short[] instead, as those are 16-bit values. If you're having trouble getting the data into an array like that, please give details... likewise if you have any other problems with the manipulation. Just be aware that until you're writing the data out as text, there's really no such concept as which base it's in, as far as the computer is concerned.
(Note that this is different for floating point values, where the data really would be different between a decimal and a double, for example... there, the base of representation is part of the data format. It's not for integers. Alternatively, you can think of all integers as just being binary until you decide to format them as text...)
From MSDN:
The hexadecimal ("X") format specifier
converts a number to a string of
hexadecimal digits. The case of the
format specifier indicates whether to
use uppercase or lowercase characters
for hexadecimal digits that are
greater than 9. For example, use "X"
to produce "ABCDEF", and "x" to
produce "abcdef". This format is
supported only for integral types.
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.
byte x = 60;
string hex = String.Format("0x{0:X4}", x);
Console.WriteLine(hex); // prints "0x003C"
Related
Now I know that converting a int to hex is simple but I have an issue here.
I have an int that I want to convert it to hex and then add another hex to it.
The simple solution is int.Tostring("X") but after my int is turned to hex, it is also turned to string so I can't add anything to it until it is turned back to int again.
So my question is; is there a way to turn a int to hex and avoid having turned it to string as well. I mean a quick way such as int.Tostring("X") but without the int being turned to string.
I mean a quick way such as int.Tostring("X") but without the int being
turned to string.
No.
Look at this way. What is the difference between those?
var i = 10;
var i = 0xA;
As a value, they are exactly same. As a representation, first one is decimal notation and the second one is hexadecimal notation. The X you use hexadecimal format specifier which generates hexadecimal notation of that numeric value.
Be aware, you can parse this hexadecimal notation string to integer anytime you want.
C# convert integer to hex and back again
There is no need to convert. Number ten is ten, write it in binary or hex, yes their representation will differ depending in which base you write them but value is same. So just add another integer to your integer - and convert the final result to hex string when you need it.
Take example. Assume you have
int x = 10 + 10; // answer is 20 or 0x14 in Hex.
Now, if you added
int x = 0x0A + 0x0A; // x == 0x14
Result would still be 0x14. See?
Numeric 10 and 0x0A have same value just they are written in different base.
Hexadecimal string although is a different beast.
In above case that could be "0x14".
For computer this would be stored as: '0', 'x', '1', '4' - four separate characters (or bytes representing these characters in some encoding). While in case with integers, it is stored as single integer (encoded in binary form).
I guess you missing the point what is HEX and what is INT. They both represent an numbers. 1, 2, 3, 4, etc.. numbers. There's a way to look at numbers: as natural numbers: INT and hexadecimal - but at the end those are same numbers. For example if you have number: 5 + 5 = 10 (int) and A (as hex) but it the same number. Just view on them are different
Hex is just a way to represent number. The same statment is true for decimal number system and binary although with exception of some custom made numbers (BigNums etd) everything will be stored as binary as long as its integer (by integer i mean not floating point number). What would you really like to do is probably performing calculations on integers and then printing them as a Hex which have been already described in this topic C# convert integer to hex and back again
The short answer: no, and there is no need.
The integer One Hundred and seventy nine (179) is B3 in hex, 179 in base-10, 10110011 in base-2 and 20122 in base-3. The base of the number doesn't change the value of it. B3, 17, 10110011, and 20122 are all the same number, they are just represented different. So it doesn't matter what base they are in as long as you do you mathematical operations on numbers in the same base it doesn't matter what the base is.
So in your case with Hex numbers, they can contain characters such as 'A','B', 'C', and so on. So when you get a value in hex if it is a number that will contain a letter in its hex representation it will have to be a string as letters are not ints. To do what you want, it would be best to convert both numbers to regular ints and then do math and convert to Hex after. The reason for this is that if you want to be able to add (or whatever operation) with them looking like hex you are going to to need to change the behavior of the desired operator on string which is a hassle.
I am currently formatting a double using the code:
myDouble.ToString("g4");
To get the first 4 decimal places. However I find this often switches over to scientific notation if the number is very large or very small. Is there an easy format string in C# to just have the first four decimal places, or zero if it is too small to be represented in that number of places?
For example, I would like:
1000 => 1000
0.1234567 => 0.1235
123456 => 123456 (Note: Not scientific notation)
0.000001234 => 0 (Note: Not scientific notation)
You can try like this:
0.1234567.ToString("0.####")
Also check Custom Numeric Format Strings
#
Replaces the "#" symbol with the corresponding digit if one is
present; otherwise, no digit appears in the result string.
Also as Jon as correctly pointed that it will round your number. See the note section
Rounding and Fixed-Point Format Strings
For fixed-point format strings
(that is, format strings that do not contain scientific notation
format characters), numbers are rounded to as many decimal places as
there are digit placeholders to the right of the decimal point.
Use the String.Format() method.
String.Format("{0:0.####}", 123.4567123); //output: 123.4567
Note: Num of #'s indicate the maximum number of digits after decimal that are required.
I agree with kjbartel comment.
I wanted exactly what the original question asked. But his question is slightly ambiguous.
The problem with ### format is it fills the slot if a digit can be represented or not.
So it does what the original question asks for some numbers but not others.
My basic need is, and it's a pretty common one, if the number is big I don't need to show decimal places. If the number is small I do want to show decimal places. Basically X number of significant digits.
The "Gn" Format will do significant digits, but it switches to scientific notation if you go over the number of digits. I don't want E notation, ever (same requirement as the question).
So I used fixed format ("Fn") but I calculate the width on the fly based on how "big" the number is.
var myFloatNumber = 123.4567;
var digits = (int) Math.Log10(myFloatNumber);
var maxDecimalplaces = 3;
var format = "F" + Math.Max(0,(maxDecimalplaces - digits));
I swear there was a way to do this in C++ (Visual Studio Flavor) in teh format statement or in C# and perhaps there is, but I can't find it.
So I came up with this. I could have converted to a string and measured length before decimal point as well. But converting it to a string twice felt wrong.
I have a string that contains the next value: 0x6007.(stringToShort)
I want to convert this string to short var, however, when I attempt to convert it the next way:
short s = ((short)Convert.ToUInt16(stringToShort, 16));
then s equals to 24583 and not to 0x6007 as I need.
Can anyone help?
Values like "0x6007" and "24583" are for human consumption. They are textual representations of a number, and are meaningful only for humans.
As far as the computer is concerned, when dealing with actual numbers, it only understands binary (and even there, only in an abstract sense…it doesn't literally store the binary digits 0s and 1s).
Any time you ask the computer what number it's thinking of, it will convert from that binary-based representation to a human-readable representation (even if binary…we puny humans can't see the state of the bits in the computer and have to ask the computer to translate them to a visual representation).
When you store the value 0x6007 in (for example) a short variable, that variable contains the value 0x6007. It also contains the value 24583. Oh, and it also contains the value 110000000000111 (binary), and the value 60007 (octal), and even the value 12287 (base twelve). Because what the computer is storing is not any of those specific representations of numbers, but rather its own internal representation of the magnitude any of those human-readable numbers represent.
But they are all the same. And when you parse a human-readable string like "0x6007", you do get exactly that value in the variable into which you stored the result, i.e. the computer's internal representation of a number having the same magnitude.
By default, if you ask the computer to tell you what that value is, it will give you the decimal representation of "24583". But if you want the hexadecimal representation, you need only ask nicely and the computer will give that to you instead (e.g. switch the numeric display format in your debugger, or use the "X" numeric format specifier in string.Format(), Console.WriteLine(), etc.).
I am using c# to read information coming out of a scale and I am getting back 6 bytes of Data. The last two contain the weight, in Hexadecimal. The way that it is set up is that if your append byte 5 on to byte 4 and convert to decimal you will get the correct weight.
I am trying to do this right now by using toString on the bytes and appending them but toString is automatically converting them from Hexadecimal to decimal. This is occurring before I can append them so I am getting incorrect weights.
Is there any way to convert a byte to a string without it being formatted from hexadecimal to decimal for you?
Use the X format string when calling ToString on your bytes to keep them in hexadecimal. You can append a number to X to specify the number of "digits" you want.
byte b = 0x0A;
b.ToString("X"); // A
b.ToString("X2"); // 0A
In C#, is there a way to convert an int value to a hex value without using the .ToString("X") method?
Your question is plain wrong (no offense intended). A number has one single value. Hex, Decimal, Binary, Octal, etc. are just different representations of one same integral number. Int32 is agnostic when it comes to what representation you choose to write it with.
So when you ask:
is there a way to convert an int value to a hex value
you are asking something thast doesn't make sense. A valid question would be: is there anyway to write a integer in hexadecimal representation that doesn't involve using .ToString("X")?
The answer is not really. Someway or the other (directly or not by you), .ToString("X") or some other flavor of ToString() will be called to correctly format the string representing the value.
And when you think of hexadecimal as a respresentation (a formatted string) of a given number, then .ToString() does make sense.
Use Convert.ToString( intValue, 16 );
It can be used to convert between any common numeric base, i.e., binary, octal, decimal and hexadecimal.