Develop Reference

How do you do a string split with 2 chars counts in C#?

I know how to do a string split if there's a letter, number, that I want to replace.
But how could I do a string.Split() by 2 char counts without replacing any existing letters, number, etc...?
Example:
string MAC = "00122345"
I want that string to output: 00:12:23:45

You could create a LINQ extension method to give you an IEnumerable<string> of parts:
public static class Extensions
{
public static IEnumerable<string> SplitNthParts(this string source, int partSize)
{
if (string.IsNullOrEmpty(source))
{
throw new ArgumentException("String cannot be null or empty.", nameof(source));
}
if (partSize < 1)
{
throw new ArgumentException("Part size has to be greater than zero.", nameof(partSize));
}
return Enumerable
.Range(0, (source.Length + partSize - 1) / partSize)
.Select(pos => source
.Substring(pos * partSize,
Math.Min(partSize, source.Length - pos * partSize)));
}
}
Usage:
var strings = new string[] {
"00122345",
"001223453"
};
foreach (var str in strings)
{
Console.WriteLine(string.Join(":", str.SplitNthParts(2)));
}
// 00:12:23:45
// 00:12:23:45:3
Explanation:
Use Enumerable.Range to get number of positions to slice string. In this case its the length of the string + chunk size - 1, since we need to get a big enough range to also fit leftover chunk sizes.
Enumerable.Select each position of slicing and get the startIndex using String.Substring using the position multiplied by 2 to move down the string every 2 characters. You will have to use Math.Min to calculate the smallest size leftover size if the string doesn't have enough characters to fit another chunk. You can calculate this by the length of the string - current position * chunk size.
String.Join the final result with ":".
You could also replace the LINQ query with yield here to increase performance for larger strings since all the substrings won't be stored in memory at once:
for (var pos = 0; pos < source.Length; pos += partSize)
{
yield return source.Substring(pos, Math.Min(partSize, source.Length - pos));
}

You can use something like this:
string newStr= System.Text.RegularExpressions.Regex.Replace(MAC, ".{2}", "$0:");
To trim the last colon, you can use something like this.
newStr.TrimEnd(':');
Microsoft Document

Try this way.
string MAC = "00122345";
MAC = System.Text.RegularExpressions.Regex.Replace(MAC,".{2}", "$0:");
MAC = MAC.Substring(0,MAC.Length-1);
Console.WriteLine(MAC);

A quite fast solution, 8-10x faster than the current accepted answer (regex solution) and 3-4x faster than the LINQ solution
public static string Format(this string s, string separator, int length)
{
StringBuilder sb = new StringBuilder();
for (int i = 0; i < s.Length; i += length)
{
sb.Append(s.Substring(i, Math.Min(s.Length - i, length)));
if (i < s.Length - length)
{
sb.Append(separator);
}
}
return sb.ToString();
}
Usage:
string result = "12345678".Format(":", 2);

Here is a one (1) line alternative using LINQ Enumerable.Aggregate.
string result = MAC.Aggregate("", (acc, c) => acc.Length % 3 == 0 ? acc += c : acc += c + ":").TrimEnd(':');

An easy to understand and simple solution.
This is a simple fast modified answer in which you can easily change the split char.
This answer also checks if the number is even or odd , to make the suitable string.Split().
input : 00122345
output : 00:12:23:45
input : 0012234
output : 00:12:23:4
//The List that keeps the pairs
List<string> MACList = new List<string>();
//Split the even number into pairs
for (int i = 1; i <= MAC.Length; i++)
{
if (i % 2 == 0)
{
MACList.Add(MAC.Substring(i - 2, 2));
}
}
//Make the preferable output
string output = "";
for (int j = 0; j < MACList.Count; j++)
{
output = output + MACList[j] + ":";
}
//Checks if the input string is even number or odd number
if (MAC.Length % 2 == 0)
{
output = output.Trim(output.Last());
}
else
{
output += MAC.Last();
}
//input : 00122345
//output : 00:12:23:45
//input : 0012234
//output : 00:12:23:4

How to swap huge string

I have huge string e.g (This is just the part, the string looks same it has just a bit different values).
string numbers = "48.7465504247904 9.16364437205161 48.7465666577545 9.16367275419435 48.746927738083 9.16430761814855 48.7471066512883 9.16462219521963 48.7471147950429";
So I have to swap the whole number e.g.
Output should be:
9.16364437205161 48.7465504247904
Also I need to swap the first and second part.
So I've tried to split the string, and then to replace the old one with the new one.
string numbers = "48.7465504247904 9.16364437205161 48.7465666577545 9.16367275419435 48.746927738083 9.16430761814855 48.7471066512883 9.16462219521963 48.7471147950429";
string output = "";
double first = 0;
double second = 0;
for (int i = 0; i < numbers.Length; i++)
{
numbers.Split(' ');
first = numbers[0];
second = numbers[1];
}
output = numbers.Replace(numbers[1], numbers[0]);
Console.WriteLine(output);
But my variable first always after the loop has the value 52.
Right now my output is: 44.7465504247904 9.16364437205161, it changed the first part, also it calculates somehow -4
.

You're not assigning anything to the value coming back from .Split and, if I read this right, you're also iterating each character in the numbers array for unclear reasons.
Using .Split is all you need ... well, and System.Linq
using System.Linq;
// ...
string SwapNumbers(string numbers) {
return numbers.Split(' ').Reverse().Join();
}
The above assumes you want to reverse the whole series of numbers. It absolutely does not swap 1,2 then swap 3,4 etc. If that's what you're looking for, it's a bit more involved and I'll add that in a second for funsies.
string SwapAlternateNumbers(string numbersInput) {
var wholeSeries = numbersInput.Split(' ').ToList();
// odd number of inputs
if (wholeSeries.Count % 2 != 0) {
throw new InvalidOperationException("I'm not handling this use case for you.");
}
var result = new StringBuilder();
for(var i = 0; i < wholeSeries.Count - 1; i += 2) {
// append the _second_ number
result.Append(wholeSeries[i+1]).Append(" ");
// append the _first_ number
result.Append(wholeSeries[i]).Append(" ");
}
// assuming you want the whole thing as a string
return result.ToString();
}
Edit: converted back to input and output string. Sorry about the enumerables; that's a difficult habit to break.

here
public static void Main()
{
string nums = "48.7465504247904 9.16364437205161 48.7465504247904 9.16364437205161";
var numbers = nums.Split(' ');
var swapped = numbers.Reverse();
Console.WriteLine("Hello World {"+string.Join(" ",swapped.ToArray())+"}");
}

C# Parse String To Double Without Scientific Notation [duplicate]

How to convert a double into a floating-point string representation without scientific notation in the .NET Framework?
"Small" samples (effective numbers may be of any size, such as 1.5E200 or 1e-200) :
3248971234698200000000000000000000000000000000
0.00000000000000000000000000000000000023897356978234562
None of the standard number formats are like this, and a custom format also doesn't seem to allow having an open number of digits after the decimal separator.
This is not a duplicate of How to convert double to string without the power to 10 representation (E-05) because the answers given there do not solve the issue at hand. The accepted solution in this question was to use a fixed point (such as 20 digits), which is not what I want. A fixed point formatting and trimming the redundant 0 doesn't solve the issue either because the max width for fixed width is 99 characters.
Note: the solution has to deal correctly with custom number formats (e.g. other decimal separator, depending on culture information).
Edit: The question is really only about displaing aforementioned numbers. I'm aware of how floating point numbers work and what numbers can be used and computed with them.

For a general-purpose¹ solution you need to preserve 339 places:
doubleValue.ToString("0." + new string('#', 339))
The maximum number of non-zero decimal digits is 16. 15 are on the right side of the decimal point. The exponent can move those 15 digits a maximum of 324 places to the right. (See the range and precision.)
It works for double.Epsilon, double.MinValue, double.MaxValue, and anything in between.
The performance will be much greater than the regex/string manipulation solutions since all formatting and string work is done in one pass by unmanaged CLR code. Also, the code is much simpler to prove correct.
For ease of use and even better performance, make it a constant:
public static class FormatStrings
{
public const string DoubleFixedPoint = "0.###################################################################################################################################################################################################################################################################################################################################################";
}
¹ Update: I mistakenly said that this was also a lossless solution. In fact it is not, since ToString does its normal display rounding for all formats except r. Live example. Thanks, #Loathing! Please see Lothing’s answer if you need the ability to roundtrip in fixed point notation (i.e, if you’re using .ToString("r") today).

I had a similar problem and this worked for me:
doubleValue.ToString("F99").TrimEnd('0')
F99 may be overkill, but you get the idea.

This is a string parsing solution where the source number (double) is converted into a string and parsed into its constituent components. It is then reassembled by rules into the full-length numeric representation. It also accounts for locale as requested.
Update: The tests of the conversions only include single-digit whole numbers, which is the norm, but the algorithm also works for something like: 239483.340901e-20
using System;
using System.Text;
using System.Globalization;
using System.Threading;
public class MyClass
{
public static void Main()
{
Console.WriteLine(ToLongString(1.23e-2));
Console.WriteLine(ToLongString(1.234e-5)); // 0.00010234
Console.WriteLine(ToLongString(1.2345E-10)); // 0.00000001002345
Console.WriteLine(ToLongString(1.23456E-20)); // 0.00000000000000000100023456
Console.WriteLine(ToLongString(5E-20));
Console.WriteLine("");
Console.WriteLine(ToLongString(1.23E+2)); // 123
Console.WriteLine(ToLongString(1.234e5)); // 1023400
Console.WriteLine(ToLongString(1.2345E10)); // 1002345000000
Console.WriteLine(ToLongString(-7.576E-05)); // -0.00007576
Console.WriteLine(ToLongString(1.23456e20));
Console.WriteLine(ToLongString(5e+20));
Console.WriteLine("");
Console.WriteLine(ToLongString(9.1093822E-31)); // mass of an electron
Console.WriteLine(ToLongString(5.9736e24)); // mass of the earth
Console.ReadLine();
}
private static string ToLongString(double input)
{
string strOrig = input.ToString();
string str = strOrig.ToUpper();
// if string representation was collapsed from scientific notation, just return it:
if (!str.Contains("E")) return strOrig;
bool negativeNumber = false;
if (str[0] == '-')
{
str = str.Remove(0, 1);
negativeNumber = true;
}
string sep = Thread.CurrentThread.CurrentCulture.NumberFormat.NumberDecimalSeparator;
char decSeparator = sep.ToCharArray()[0];
string[] exponentParts = str.Split('E');
string[] decimalParts = exponentParts[0].Split(decSeparator);
// fix missing decimal point:
if (decimalParts.Length==1) decimalParts = new string[]{exponentParts[0],"0"};
int exponentValue = int.Parse(exponentParts[1]);
string newNumber = decimalParts[0] + decimalParts[1];
string result;
if (exponentValue > 0)
{
result =
newNumber +
GetZeros(exponentValue - decimalParts[1].Length);
}
else // negative exponent
{
result =
"0" +
decSeparator +
GetZeros(exponentValue + decimalParts[0].Length) +
newNumber;
result = result.TrimEnd('0');
}
if (negativeNumber)
result = "-" + result;
return result;
}
private static string GetZeros(int zeroCount)
{
if (zeroCount < 0)
zeroCount = Math.Abs(zeroCount);
StringBuilder sb = new StringBuilder();
for (int i = 0; i < zeroCount; i++) sb.Append("0");
return sb.ToString();
}
}

You could cast the double to decimal and then do ToString().
(0.000000005).ToString() // 5E-09
((decimal)(0.000000005)).ToString() // 0,000000005
I haven't done performance testing which is faster, casting from 64-bit double to 128-bit decimal or a format string of over 300 chars. Oh, and there might possibly be overflow errors during conversion, but if your values fit a decimal this should work fine.
Update: The casting seems to be a lot faster. Using a prepared format string as given in the other answer, formatting a million times takes 2.3 seconds and casting only 0.19 seconds. Repeatable. That's 10x faster. Now it's only about the value range.

This is what I've got so far, seems to work, but maybe someone has a better solution:
private static readonly Regex rxScientific = new Regex(#"^(?<sign>-?)(?<head>\d+)(\.(?<tail>\d*?)0*)?E(?<exponent>[+\-]\d+)$", RegexOptions.IgnoreCase|RegexOptions.ExplicitCapture|RegexOptions.CultureInvariant);
public static string ToFloatingPointString(double value) {
return ToFloatingPointString(value, NumberFormatInfo.CurrentInfo);
}
public static string ToFloatingPointString(double value, NumberFormatInfo formatInfo) {
string result = value.ToString("r", NumberFormatInfo.InvariantInfo);
Match match = rxScientific.Match(result);
if (match.Success) {
Debug.WriteLine("Found scientific format: {0} => [{1}] [{2}] [{3}] [{4}]", result, match.Groups["sign"], match.Groups["head"], match.Groups["tail"], match.Groups["exponent"]);
int exponent = int.Parse(match.Groups["exponent"].Value, NumberStyles.Integer, NumberFormatInfo.InvariantInfo);
StringBuilder builder = new StringBuilder(result.Length+Math.Abs(exponent));
builder.Append(match.Groups["sign"].Value);
if (exponent >= 0) {
builder.Append(match.Groups["head"].Value);
string tail = match.Groups["tail"].Value;
if (exponent < tail.Length) {
builder.Append(tail, 0, exponent);
builder.Append(formatInfo.NumberDecimalSeparator);
builder.Append(tail, exponent, tail.Length-exponent);
} else {
builder.Append(tail);
builder.Append('0', exponent-tail.Length);
}
} else {
builder.Append('0');
builder.Append(formatInfo.NumberDecimalSeparator);
builder.Append('0', (-exponent)-1);
builder.Append(match.Groups["head"].Value);
builder.Append(match.Groups["tail"].Value);
}
result = builder.ToString();
}
return result;
}
// test code
double x = 1.0;
for (int i = 0; i < 200; i++) {
x /= 10;
}
Console.WriteLine(x);
Console.WriteLine(ToFloatingPointString(x));

The problem using #.###...### or F99 is that it doesn't preserve precision at the ending decimal places, e.g:
String t1 = (0.0001/7).ToString("0." + new string('#', 339)); // 0.0000142857142857143
String t2 = (0.0001/7).ToString("r"); // 1.4285714285714287E-05
The problem with DecimalConverter.cs is that it is slow. This code is the same idea as Sasik's answer, but twice as fast. Unit test method at bottom.
public static class RoundTrip {
private static String[] zeros = new String[1000];
static RoundTrip() {
for (int i = 0; i < zeros.Length; i++) {
zeros[i] = new String('0', i);
}
}
private static String ToRoundTrip(double value) {
String str = value.ToString("r");
int x = str.IndexOf('E');
if (x < 0) return str;
int x1 = x + 1;
String exp = str.Substring(x1, str.Length - x1);
int e = int.Parse(exp);
String s = null;
int numDecimals = 0;
if (value < 0) {
int len = x - 3;
if (e >= 0) {
if (len > 0) {
s = str.Substring(0, 2) + str.Substring(3, len);
numDecimals = len;
}
else
s = str.Substring(0, 2);
}
else {
// remove the leading minus sign
if (len > 0) {
s = str.Substring(1, 1) + str.Substring(3, len);
numDecimals = len;
}
else
s = str.Substring(1, 1);
}
}
else {
int len = x - 2;
if (len > 0) {
s = str[0] + str.Substring(2, len);
numDecimals = len;
}
else
s = str[0].ToString();
}
if (e >= 0) {
e = e - numDecimals;
String z = (e < zeros.Length ? zeros[e] : new String('0', e));
s = s + z;
}
else {
e = (-e - 1);
String z = (e < zeros.Length ? zeros[e] : new String('0', e));
if (value < 0)
s = "-0." + z + s;
else
s = "0." + z + s;
}
return s;
}
private static void RoundTripUnitTest() {
StringBuilder sb33 = new StringBuilder();
double[] values = new [] { 123450000000000000.0, 1.0 / 7, 10000000000.0/7, 100000000000000000.0/7, 0.001/7, 0.0001/7, 100000000000000000.0, 0.00000000001,
1.23e-2, 1.234e-5, 1.2345E-10, 1.23456E-20, 5E-20, 1.23E+2, 1.234e5, 1.2345E10, -7.576E-05, 1.23456e20, 5e+20, 9.1093822E-31, 5.9736e24, double.Epsilon };
foreach (int sign in new [] { 1, -1 }) {
foreach (double val in values) {
double val2 = sign * val;
String s1 = val2.ToString("r");
String s2 = ToRoundTrip(val2);
double val2_ = double.Parse(s2);
double diff = Math.Abs(val2 - val2_);
if (diff != 0) {
throw new Exception("Value {0} did not pass ToRoundTrip.".Format2(val.ToString("r")));
}
sb33.AppendLine(s1);
sb33.AppendLine(s2);
sb33.AppendLine();
}
}
}
}

The obligatory Logarithm-based solution. Note that this solution, because it involves doing math, may reduce the accuracy of your number a little bit. Not heavily tested.
private static string DoubleToLongString(double x)
{
int shift = (int)Math.Log10(x);
if (Math.Abs(shift) <= 2)
{
return x.ToString();
}
if (shift < 0)
{
double y = x * Math.Pow(10, -shift);
return "0.".PadRight(-shift + 2, '0') + y.ToString().Substring(2);
}
else
{
double y = x * Math.Pow(10, 2 - shift);
return y + "".PadRight(shift - 2, '0');
}
}
Edit: If the decimal point crosses non-zero part of the number, this algorithm will fail miserably. I tried for simple and went too far.

In the old days when we had to write our own formatters, we'd isolate the mantissa and exponent and format them separately.
In this article by Jon Skeet (https://csharpindepth.com/articles/FloatingPoint) he provides a link to his DoubleConverter.cs routine that should do exactly what you want. Skeet also refers to this at extracting mantissa and exponent from double in c#.

I have just improvised on the code above to make it work for negative exponential values.
using System;
using System.Text.RegularExpressions;
using System.IO;
using System.Text;
using System.Threading;
namespace ConvertNumbersInScientificNotationToPlainNumbers
{
class Program
{
private static string ToLongString(double input)
{
string str = input.ToString(System.Globalization.CultureInfo.InvariantCulture);
// if string representation was collapsed from scientific notation, just return it:
if (!str.Contains("E")) return str;
var positive = true;
if (input < 0)
{
positive = false;
}
string sep = Thread.CurrentThread.CurrentCulture.NumberFormat.NumberDecimalSeparator;
char decSeparator = sep.ToCharArray()[0];
string[] exponentParts = str.Split('E');
string[] decimalParts = exponentParts[0].Split(decSeparator);
// fix missing decimal point:
if (decimalParts.Length == 1) decimalParts = new string[] { exponentParts[0], "0" };
int exponentValue = int.Parse(exponentParts[1]);
string newNumber = decimalParts[0].Replace("-", "").
Replace("+", "") + decimalParts[1];
string result;
if (exponentValue > 0)
{
if (positive)
result =
newNumber +
GetZeros(exponentValue - decimalParts[1].Length);
else
result = "-" +
newNumber +
GetZeros(exponentValue - decimalParts[1].Length);
}
else // negative exponent
{
if (positive)
result =
"0" +
decSeparator +
GetZeros(exponentValue + decimalParts[0].Replace("-", "").
Replace("+", "").Length) + newNumber;
else
result =
"-0" +
decSeparator +
GetZeros(exponentValue + decimalParts[0].Replace("-", "").
Replace("+", "").Length) + newNumber;
result = result.TrimEnd('0');
}
float temp = 0.00F;
if (float.TryParse(result, out temp))
{
return result;
}
throw new Exception();
}
private static string GetZeros(int zeroCount)
{
if (zeroCount < 0)
zeroCount = Math.Abs(zeroCount);
StringBuilder sb = new StringBuilder();
for (int i = 0; i < zeroCount; i++) sb.Append("0");
return sb.ToString();
}
public static void Main(string[] args)
{
//Get Input Directory.
Console.WriteLine(#"Enter the Input Directory");
var readLine = Console.ReadLine();
if (readLine == null)
{
Console.WriteLine(#"Enter the input path properly.");
return;
}
var pathToInputDirectory = readLine.Trim();
//Get Output Directory.
Console.WriteLine(#"Enter the Output Directory");
readLine = Console.ReadLine();
if (readLine == null)
{
Console.WriteLine(#"Enter the output path properly.");
return;
}
var pathToOutputDirectory = readLine.Trim();
//Get Delimiter.
Console.WriteLine("Enter the delimiter;");
var columnDelimiter = (char)Console.Read();
//Loop over all files in the directory.
foreach (var inputFileName in Directory.GetFiles(pathToInputDirectory))
{
var outputFileWithouthNumbersInScientificNotation = string.Empty;
Console.WriteLine("Started operation on File : " + inputFileName);
if (File.Exists(inputFileName))
{
// Read the file
using (var file = new StreamReader(inputFileName))
{
string line;
while ((line = file.ReadLine()) != null)
{
String[] columns = line.Split(columnDelimiter);
var duplicateLine = string.Empty;
int lengthOfColumns = columns.Length;
int counter = 1;
foreach (var column in columns)
{
var columnDuplicate = column;
try
{
if (Regex.IsMatch(columnDuplicate.Trim(),
#"^[+-]?[0-9]+(\.[0-9]+)?[E]([+-]?[0-9]+)$",
RegexOptions.IgnoreCase))
{
Console.WriteLine("Regular expression matched for this :" + column);
columnDuplicate = ToLongString(Double.Parse
(column,
System.Globalization.NumberStyles.Float));
Console.WriteLine("Converted this no in scientific notation " +
"" + column + " to this number " +
columnDuplicate);
}
}
catch (Exception)
{
}
duplicateLine = duplicateLine + columnDuplicate;
if (counter != lengthOfColumns)
{
duplicateLine = duplicateLine + columnDelimiter.ToString();
}
counter++;
}
duplicateLine = duplicateLine + Environment.NewLine;
outputFileWithouthNumbersInScientificNotation = outputFileWithouthNumbersInScientificNotation + duplicateLine;
}
file.Close();
}
var outputFilePathWithoutNumbersInScientificNotation
= Path.Combine(pathToOutputDirectory, Path.GetFileName(inputFileName));
//Create Directory If it does not exist.
if (!Directory.Exists(pathToOutputDirectory))
Directory.CreateDirectory(pathToOutputDirectory);
using (var outputFile =
new StreamWriter(outputFilePathWithoutNumbersInScientificNotation))
{
outputFile.Write(outputFileWithouthNumbersInScientificNotation);
outputFile.Close();
}
Console.WriteLine("The transformed file is here :" +
outputFilePathWithoutNumbersInScientificNotation);
}
}
}
}
}
This code takes an input directory and based on the delimiter converts all values in scientific notation to numeric format.
Thanks

try this one:
public static string DoubleToFullString(double value,
NumberFormatInfo formatInfo)
{
string[] valueExpSplit;
string result, decimalSeparator;
int indexOfDecimalSeparator, exp;
valueExpSplit = value.ToString("r", formatInfo)
.ToUpper()
.Split(new char[] { 'E' });
if (valueExpSplit.Length > 1)
{
result = valueExpSplit[0];
exp = int.Parse(valueExpSplit[1]);
decimalSeparator = formatInfo.NumberDecimalSeparator;
if ((indexOfDecimalSeparator
= valueExpSplit[0].IndexOf(decimalSeparator)) > -1)
{
exp -= (result.Length - indexOfDecimalSeparator - 1);
result = result.Replace(decimalSeparator, "");
}
if (exp >= 0) result += new string('0', Math.Abs(exp));
else
{
exp = Math.Abs(exp);
if (exp >= result.Length)
{
result = "0." + new string('0', exp - result.Length)
+ result;
}
else
{
result = result.Insert(result.Length - exp, decimalSeparator);
}
}
}
else result = valueExpSplit[0];
return result;
}

Being millions of programmers world wide, it's always a good practice to try search if someone has bumped into your problem already. Sometimes there's solutions are garbage, which means it's time to write your own, and sometimes there are great, such as the following:
http://www.yoda.arachsys.com/csharp/DoubleConverter.cs
(details: http://www.yoda.arachsys.com/csharp/floatingpoint.html)

string strdScaleFactor = dScaleFactor.ToString(); // where dScaleFactor = 3.531467E-05
decimal decimalScaleFactor = Decimal.Parse(strdScaleFactor, System.Globalization.NumberStyles.Float);

I don't know if my answer to the question can still be helpful. But in this case I suggest the "decomposition of the double variable into decimal places" to store it in an Array / Array of data of type String.
This process of decomposition and storage in parts (number by number) from double to string, would basically work with the use of two loops and an "alternative" (if you thought of workaround, I think you got it), where the first loop will extract the values from double without converting to String, resulting in blessed scientific notation and storing number by number in an Array. And this will be done using MOD - the same method to check a palindrome number, which would be for example:
String[] Array_ = new double[ **here you will put an extreme value of places your DOUBLE can reach, you must have a prediction**];
for (int i = 0, variableDoubleMonstrous > 0, i++){
x = variableDoubleMonstrous %10;
Array_[i] = x;
variableDoubleMonstrous /= 10;
}
And the second loop to invert the Array values ​​(because in this process of checking a palindrome, the values ​​invert from the last place, to the first, from the penultimate to the second and so on. Remember?) to get the original value:
String[] ArrayFinal = new String[the same number of "places" / indices of the other Array / Data array];
int lengthArray = Array_.Length;
for (int i = 0, i < Array_.Length, i++){
FinalArray[i] = Array_[lengthArray - 1];
lengthArray--;
}
***Warning: There's a catch that I didn't pay attention to. In that case there will be no "." (floating point decimal separator or double), so this solution is not generalized. But if it is really important to use decimal separators, unfortunately the only possibility (If done well, it will have a great performance) is:
**Use a routine to get the position of the decimal point of the original value, the one with scientific notation - the important thing is that you know that this floating point is before a number such as the "Length" position x, and after a number such as the y position - extracting each digit using the loops - as shown above - and at the end "export" the data from the last Array to another one, including the decimal place divider (the comma, or the period , if variable decimal, double or float) in the imaginary position that was in the original variable, in the "real" position of that matrix.
*** The concept of position is, find out how many numbers occur before the decimal point, so with this information you will be able to store in the String Array the point in the real position.
NEEDS THAT CAN BE MADE:
But then you ask:
But what about when I'm going to convert String to a floating point value?
My answer is that you use the second matrix of this entire process (the one that receives the inversion of the first matrix that obtains the numbers by the palindrome method) and use it for the conversion, but always making sure, when necessary, of the position of the decimal place in future situations, in case this conversion (Double -> String) is needed again.
But what if the problem is to use the value of the converted Double (Array of Strings) in a calculation. Then in this case you went around in circles. Well, the original variable will work anyway even with scientific notation. The only difference between floating point and decimal variable types is in the rounding of values, which depending on the purpose, it will only be necessary to change the type of data used, but it is dangerous to have a significant loss of information, look here

I could be wrong, but isn't it like this?
data.ToString("n");
http://msdn.microsoft.com/en-us/library/dwhawy9k.aspx

i think you need only to use IFormat with
ToString(doubleVar, System.Globalization.NumberStyles.Number)
example:
double d = double.MaxValue;
string s = d.ToString(d, System.Globalization.NumberStyles.Number);

My solution was using the custom formats.
try this:
double d;
d = 1234.12341234;
d.ToString("#########0.#########");

Just to build on what jcasso said what you can do is to adjust your double value by changing the exponent so that your favorite format would do it for you, apply the format, and than pad the result with zeros to compensate for the adjustment.

This works fine for me...
double number = 1.5E+200;
string s = number.ToString("#");
//Output: "150000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000"

Compare numeric values as string

I have a method which gets two string. These strings can contain numbers, ASCII chars or both at the same time.
The algorithm works like this:
Split both strings into char Arrays A and B.
Try to parse element Ai and Bi to an int
Compare element Ai with element Bi, in case of integers use direct comparison, in case of chars use ordinal string comparison.
Do work based on the result
Now, I'm wondering: Do I really need to parse the elements to int? I simply could compare each element in an ordinal string comparison and would get the same result, right?
What are the performance implications here? Is parsing and normal comparison faster than ordinal string comparison? Is it slower?
Is my assumption (using ordinal string comparison instead of parsing and comparing) correct?
Here is the method in question:
internal static int CompareComponentString(this string componentString, string other)
{
bool componentEmpty = string.IsNullOrWhiteSpace(componentString);
bool otherEmtpy = string.IsNullOrWhiteSpace(other);
if (componentEmpty && otherEmtpy)
{
return 0;
}
if (componentEmpty)
{
return -1;
}
if (otherEmtpy)
{
return 1;
}
string[] componentParts = componentString.Split(new[] { '.' }, StringSplitOptions.RemoveEmptyEntries);
string[] otherParts = other.Split(new[] { '.' }, StringSplitOptions.RemoveEmptyEntries);
for (int i = 0; i < Math.Min(componentParts.Length, otherParts.Length); i++)
{
string componentChar = componentParts[i];
string otherChar = otherParts[i];
int componentNumVal, otherNumVal;
bool componentIsNum = int.TryParse(componentChar, out componentNumVal);
bool otherIsNum = int.TryParse(otherChar, out otherNumVal);
if (componentIsNum && otherIsNum)
{
if (componentNumVal.CompareTo(otherNumVal) == 0)
{
continue;
}
return componentNumVal.CompareTo(otherNumVal);
}
else
{
if (componentIsNum)
{
return -1;
}
if (otherIsNum)
{
return 1;
}
int comp = string.Compare(componentChar, otherChar, StringComparison.OrdinalIgnoreCase);
if (comp != 0)
{
return comp;
}
}
}
return componentParts.Length.CompareTo(otherParts.Length);
}
This are strings that might be used. I might add only the part after the minus sign is used.
1.0.0-alpha
1.0.0-alpha.1
1.0.0-alpha.beta
1.0.0-beta.2

With this method you can create a compare string for each of your string. These strings are comparable by simple alphanumeric comparison.
Assumptions:
There is a minus in the string separating the common part and the indiv part
before the minus is always a substring of three integer values divided by a dot
These integer values are not higher than 999 (look at variable "MaxWidth1")
behind the minus is another substring consisting of several parts, also divided by a dot
The second substring's parts may be numeric or alphanumeric with a max. width of 7 (look at "MaxWidth2")
The second substring consists of max. 5 parts (MaxIndivParts)
Put this method wherever you want:
public string VersionNumberCompareString(string versionNumber, int MaxWidth1=3, int MaxWidth2=7,int MaxIndivParts=5){
string result = null;
int posMinus = versionNumber.IndexOf('-');
string part1 = versionNumber.Substring(0, posMinus);
string part2 = versionNumber.Substring(posMinus+1);
var integerValues=part1.Split('.');
result = integerValues[0].PadLeft(MaxWidth1, '0');
result += integerValues[1].PadLeft(MaxWidth1, '0');
result += integerValues[2].PadLeft(MaxWidth1, '0');
var alphaValues = part2.Split('.');
for (int i = 0; i < MaxIndivParts;i++ ) {
if (i <= alphaValues.GetUpperBound(0)) {
var s = alphaValues[i];
int casted;
if (int.TryParse(s, out casted)) //if int: treat as number
result += casted.ToString().PadLeft(MaxWidth2, '0');
else //treat as string
result += s.PadRight(MaxWidth2, ' ');
}
else
result += new string(' ', MaxWidth2);
}
return result; }
You call it like this:
var s1 = VersionNumberCompareString("1.3.0-alpha.1.12");
//"001003000alpha 00000010000012 "
var s2 = VersionNumberCompareString("0.11.4-beta");
//"000011004beta "
var s3 = VersionNumberCompareString("2.10.11-beta.2");
//"002010011beta 0000002 "
Be aware of the final " sign. All strings are of the same length!
Hope this helps...

that's .net comparison logic for ascii strings -
private unsafe static int CompareOrdinalIgnoreCaseHelper(String strA, String strB)
{
Contract.Requires(strA != null);
Contract.Requires(strB != null);
Contract.EndContractBlock();
int length = Math.Min(strA.Length, strB.Length);
fixed (char* ap = &strA.m_firstChar) fixed (char* bp = &strB.m_firstChar)
{
char* a = ap;
char* b = bp;
while (length != 0)
{
int charA = *a;
int charB = *b;
Contract.Assert((charA | charB) <= 0x7F, "strings have to be ASCII");
// uppercase both chars - notice that we need just one compare per char
if ((uint)(charA - 'a') <= (uint)('z' - 'a')) charA -= 0x20;
if ((uint)(charB - 'a') <= (uint)('z' - 'a')) charB -= 0x20;
//Return the (case-insensitive) difference between them.
if (charA != charB)
return charA - charB;
// Next char
a++; b++;
length--;
}
return strA.Length - strB.Length;
}
}
having said that, Unless you have a strict performance constaint, i would say if you get the same result from an already implemented & tested function, its better to reuse it and not to reinvent the wheel.
It saves so much time in implementation, unit testing, debugging & bug fixing time. & helps keep the software simple.

Add separator to string at every N characters?

I have a string which contains binary digits. How to separate string after each 8 digit?
Suppose the string is:
string x = "111111110000000011111111000000001111111100000000";
I want to add a separator like ,(comma) after each 8 character.
output should be :
"11111111,00000000,11111111,00000000,11111111,00000000,"
Then I want to send it to a list<> last 8 char 1st then the previous 8 chars(excepting ,) and so on.
How can I do this?

Regex.Replace(myString, ".{8}", "$0,");
If you want an array of eight-character strings, then the following is probably easier:
Regex.Split(myString, "(?<=^(.{8})+)");
which will split the string only at points where a multiple of eight characters precede it.

Try this:
var s = "111111110000000011111111000000001111111100000000";
var list = Enumerable
.Range(0, s.Length/8)
.Select(i => s.Substring(i*8, 8));
var res = string.Join(",", list);

There's another Regex approach:
var str = "111111110000000011111111000000001111111100000000";
# for .NET 4
var res = String.Join(",",Regex.Matches(str, #"\d{8}").Cast<Match>());
# for .NET 3.5
var res = String.Join(",", Regex.Matches(str, #"\d{8}")
.OfType<Match>()
.Select(m => m.Value).ToArray());

...or old school:
public static List<string> splitter(string in, out string csv)
{
if (in.length % 8 != 0) throw new ArgumentException("in");
var lst = new List<string>(in/8);
for (int i=0; i < in.length / 8; i++) lst.Add(in.Substring(i*8,8));
csv = string.Join(",", lst); //This we want in input order (I believe)
lst.Reverse(); //As we want list in reverse order (I believe)
return lst;
}

Ugly but less garbage:
private string InsertStrings(string s, int insertEvery, char insert)
{
char[] ins = s.ToCharArray();
int length = s.Length + (s.Length / insertEvery);
if (ins.Length % insertEvery == 0)
{
length--;
}
var outs = new char[length];
long di = 0;
long si = 0;
while (si < s.Length - insertEvery)
{
Array.Copy(ins, si, outs, di, insertEvery);
si += insertEvery;
di += insertEvery;
outs[di] = insert;
di ++;
}
Array.Copy(ins, si, outs, di, ins.Length - si);
return new string(outs);
}
String overload:
private string InsertStrings(string s, int insertEvery, string insert)
{
char[] ins = s.ToCharArray();
char[] inserts = insert.ToCharArray();
int insertLength = inserts.Length;
int length = s.Length + (s.Length / insertEvery) * insert.Length;
if (ins.Length % insertEvery == 0)
{
length -= insert.Length;
}
var outs = new char[length];
long di = 0;
long si = 0;
while (si < s.Length - insertEvery)
{
Array.Copy(ins, si, outs, di, insertEvery);
si += insertEvery;
di += insertEvery;
Array.Copy(inserts, 0, outs, di, insertLength);
di += insertLength;
}
Array.Copy(ins, si, outs, di, ins.Length - si);
return new string(outs);
}

If I understand your last requirement correctly (it's not clear to me if you need the intermediate comma-delimited string or not), you could do this:
var enumerable = "111111110000000011111111000000001111111100000000".Batch(8).Reverse();
By utilizing morelinq.

Here my two little cents too. An implementation using StringBuilder:
public static string AddChunkSeparator (string str, int chunk_len, char separator)
{
if (str == null || str.Length < chunk_len) {
return str;
}
StringBuilder builder = new StringBuilder();
for (var index = 0; index < str.Length; index += chunk_len) {
builder.Append(str, index, chunk_len);
builder.Append(separator);
}
return builder.ToString();
}
You can call it like this:
string data = "111111110000000011111111000000001111111100000000";
string output = AddChunkSeparator(data, 8, ',');

One way using LINQ:
string data = "111111110000000011111111000000001111111100000000";
const int separateOnLength = 8;
string separated = new string(
data.Select((x,i) => i > 0 && i % separateOnLength == 0 ? new [] { ',', x } : new [] { x })
.SelectMany(x => x)
.ToArray()
);

I did it using Pattern & Matcher as following way:
fun addAnyCharacter(input: String, insertion: String, interval: Int): String {
val pattern = Pattern.compile("(.{$interval})", Pattern.DOTALL)
val matcher = pattern.matcher(input)
return matcher.replaceAll("$1$insertion")
}
Where:
input indicates Input string. Check results section.
insertion indicates Insert string between those characters. For example comma (,), start(*), hash(#).
interval indicates at which interval you want to add insertion character.
input indicates Input string. Check results section. Check results section; here I've added insertion at every 4th character.
Results:
I/P: 1234XXXXXXXX5678 O/P: 1234 XXXX XXXX 5678
I/P: 1234567812345678 O/P: 1234 5678 1234 5678
I/P: ABCDEFGHIJKLMNOP O/P: ABCD EFGH IJKL MNOP
Hope this helps.

As of .Net 6, you can simply use the IEnumerable.Chunk method (Which splits elements of a sequence into chunks) then reconcatenate the chunks using String.Join.
var text = "...";
string.Join(',', text.Chunk(size: 6).Select(x => new string(x)));

This is much faster without copying array (this version inserts space every 3 digits but you can adjust it to your needs)
public string GetString(double valueField)
{
char[] ins = valueField.ToString().ToCharArray();
int length = ins.Length + (ins.Length / 3);
if (ins.Length % 3 == 0)
{
length--;
}
char[] outs = new char[length];
int i = length - 1;
int j = ins.Length - 1;
int k = 0;
do
{
if (k == 3)
{
outs[i--] = ' ';
k = 0;
}
else
{
outs[i--] = ins[j--];
k++;
}
}
while (i >= 0);
return new string(outs);
}

For every 1 character, you could do this one-liner:
string.Join(".", "1234".ToArray()) //result: 1.2.3.4

If you intend to create your own function to acheive this without using regex or pattern matching methods, you can create a simple function like this:
String formatString(String key, String seperator, int afterEvery){
String formattedKey = "";
for(int i=0; i<key.length(); i++){
formattedKey += key.substring(i,i+1);
if((i+1)%afterEvery==0)
formattedKey += seperator;
}
if(formattedKey.endsWith("-"))
formattedKey = formattedKey.substring(0,formattedKey.length()-1);
return formattedKey;
}
Calling the mothod like this
formatString("ABCDEFGHIJKLMNOPQRST", "-", 4)
Would result in the return string as this
ABCD-EFGH-IJKL-MNOP-QRST

A little late to the party, but here's a simplified LINQ expression to break an input string x into groups of n separated by another string sep:
string sep = ",";
int n = 8;
string result = String.Join(sep, x.InSetsOf(n).Select(g => new String(g.ToArray())));
A quick rundown of what's happening here:
x is being treated as an IEnumerable<char>, which is where the InSetsOf extension method comes in.
InSetsOf(n) groups characters into an IEnumerable of IEnumerable -- each entry in the outer grouping contains an inner group of n characters.
Inside the Select method, each group of n characters is turned back into a string by using the String() constructor that takes an array of chars.
The result of Select is now an IEnumerable<string>, which is passed into String.Join to interleave the sep string, just like any other example.

I am more than late with my answer but you can use this one:
static string PutLineBreak(string str, int split)
{
for (int a = 1; a <= str.Length; a++)
{
if (a % split == 0)
str = str.Insert(a, "\n");
}
return str;
}