How do I convert a 10 digit number to a hex string in c#?
Note: if the number is less than 10 digits, I want to add padding? example
the number is 1, I want my string to be 0000000001.
Use a standard format string:
string paddedHex = myNumber.ToString("x10");
See the x format specifier.
Related
I'm writing some code to display a number for a report. The number can range from 1. something to thousands, so the amount of precision I need to display depends on the value.
I would like to be able to pass something in .ToString() which will give me at least 3 digits - a mixture of the integer part and the decimal part.
Ex:
1.2345 -> "1.23"
21.552 -> "21.5"
19232.12 -> "19232"
Using 000 as a format doesn't work, since it doesn't show any decimals, neither does 0.000 - which shows too many decimals when the whole part is larger than 10.
You could write an extension method for this:
public static string ToCustomString(this double d, int minDigits = 3)
{
// Get the number of digits of the integer part of the number.
int intDigits = (int)Math.Floor(Math.Log10(d) + 1);
// Calculate the decimal places to be used.
int decimalPlaces = Math.Max(0, minDigits - intDigits);
return d.ToString($"0.{new string('0', decimalPlaces)}");
}
Usage:
Console.WriteLine(1.2345.ToCustomString()); // 1.23
Console.WriteLine(21.552.ToCustomString()); // 21.6
Console.WriteLine(19232.12.ToCustomString()); // 19232
Console.WriteLine(1.2345.ToCustomString(minDigits:4)); // 1.235
Try it online.
I don't think this can be done with ToString() alone.
Instead, start by formatting the number with 2 trailing digits, then truncate as necessary:
static string FormatNumber3Digits(double n)
{
// format number with two trailing decimals
var numberString = n.ToString("0.00");
if(numberString.Length > 5)
// if resulting string is longer than 5 chars it means we have 3 or more digits occur before the decimal separator
numberString = numberString.Remove(numberString.Length - 3);
else if(numberString.Length == 5)
// if it's exactly 5 we just need to cut off the last digit to get NN.N
numberString = numberString.Remove(numberString.Length - 1);
return numberString;
}
Here's a regex, that will give you three digits of any number (if there's no decimal point, then all digits are matched):
#"^(?:\d\.\d{1,2}|\d{2}\.\d|[^.]+)"
Explanation:
^ match from start of string
either
\d\.\d{1,2} a digit followed by a dot followed by 1 or 2 digits
or
\d{2}\.\d 2 digits followed by a dot and 1 digit
or
[^.]+ any number of digits not up to a dot.
First divide your number and then call ToString() before the regex.
Simple way to implement this just write
ToString("f2") for two decimal number just change this fnumber to get your required number of decimal values with integer values also.
I have a double number:
element.MaxAllowableConcLimitPpm = 0.077724795640326971;
I need to display it as
7.7725e-2
when I try to use it:
element.MaxAllowableConcLimitPpm.ToString("e4", CultureInfo.InvariantCulture)
it returns
7.7725e-002
How to say that mantissa should have one symbol instead of 3 ?
Format like this:
.ToString("0.0000e0")
returns
5.0000e2
instead of
5.0000e+2
You have to use a custom numeric format string - standard numeric format strings always have at least three digits in the exponent.
Example with a custom string:
using System;
public class Test
{
static void Main()
{
double value = 0.077724795640326971;
Console.WriteLine(value.ToString("0.0000e+0")); // 7.7725e-2
}
}
From the documentation for standard numeric format strings (emphasis mine):
The case of the format specifier indicates whether to prefix the exponent with an "E" or an "e". The exponent always consists of a plus or minus sign and a minimum of three digits. The exponent is padded with zeros to meet this minimum, if required.
This question already has answers here:
.NET String.Format() to add commas in thousands place for a number
(23 answers)
Closed 8 years ago.
Using the below code I am formatting the double number with group seperator like if the number is 5000, it should display like 5,000 and if the number is only 5 it should display only 5 but here its displaying 05 how can I avoid this?
double doubleNumTest = 5;
string str = doubleNumTest.ToString("0,0", CultureInfo.InvariantCulture);
You can use the numeric format specifier with zero fractional digits; N0:
string str = doubleNumTest.ToString("N0", CultureInfo.InvariantCulture);
Try this:
string str = doubleNumTest.ToString("#,0", CultureInfo.InvariantCulture);
Use Digit placeholder:
Replaces the "#" symbol with the corresponding digit if one is
present; otherwise, no digit appears in the result string.
More information: The "#" Custom Specifier.
double doubleNumTest = 5;
string str = doubleNumTest.ToString("#,#", CultureInfo.InvariantCulture);
double doubleNumTest = 500;
string str = doubleNumTest.ToString("#,#", CultureInfo.InvariantCulture);
double doubleNumTest = 50000;
string str = doubleNumTest.ToString("#,#", CultureInfo.InvariantCulture);
Output:
5
500
50,000
See here for the custom numeric formats that can be passed to this method.
The format string that you are using is telling it to print the leading zero's, try using the # instead of the 0.
from MSDN
"0" Zero placeholder Replaces the zero with the corresponding digit if one is present; otherwise, zero appears in the result string.
"#" Digit placeholder Replaces the "#" symbol with the corresponding digit if one is present; otherwise, no digit appears in the result string.
I want to convert an integer to 3 character ascii string. For example if integer is 123, the my ascii string will also be "123". If integer is 1, then my ascii will be "001". If integer is 45, then my ascii string will be "045". So far I've tried Convert.ToString but could not get the result. How?
int myInt = 52;
string myString = myInt.ToString("000");
myString is "052" now. Hope it will help
Answer for the new question:
You're looking for String.PadLeft. Use it like myInteger.ToString().PadLeft(3, '0'). Or, simply use the "0" custom format specifier. Like myInteger.ToString("000").
Answer for the original question, returning strings like "0x31 0x32 0x33":
String.Join(" ",myInteger.ToString().PadLeft(3,'0').Select(x=>String.Format("0x{0:X}",(int)x))
Explanation:
The first ToString() converts your integer 123 into its string representation "123".
PadLeft(3,'0') pads the returned string out to three characters using a 0 as the padding character
Strings are enumerable as an array of char, so .Select selects into this array
For each character in the array, format it as 0x then the value of the character
Casting the char to int will allow you to get the ASCII value (you may be able to skip this cast, I am not sure)
The "X" format string converts a numeric value to hexadecimal
String.Join(" ", ...) puts it all back together again with spaces in between
It depends on if you actually want ASCII characters or if you want text. The below code will do both.
int value = 123;
// Convert value to text, adding leading zeroes.
string text = value.ToString().PadLeft(3, '0');
// Convert text to ASCII.
byte[] ascii = Encoding.ASCII.GetBytes(text);
Realise that .Net doesn't use ASCII for text manipulation. You can save ASCII to a file, but if you're using string objects, they're encoded in UTF-16.
I want to generate a 4 character hex number.
To generate a hex number you can use
string.format("{0:X}", number)
and to generate a 4 char string you can use
string.format("{0:0000}", number)
Is there any way to combine them?
I'm assuming you mean: 4-digit hexadecimal number.
If so, then yes:
string.Format("{0:X4}", number)
should do the trick.
Have you tried:
string hex = string.Format("{0:X4}", number);
? Alternatively, if you don't need it to be part of a composite pattern, it's simpler to write:
string hex = number.ToString("X4");