Develop Reference

How do I add integers to char[] array?

So I have to write a code that picks our random numbers from 1 to 100 and add them to a char[] array. But I'm having some difficulty doing so as I can only add the numbers to the array if I convert them to a char using (char) which changes the number. Can someone please help me?
Thanks,
public char[] CreationListe(int nmbrevaleurTirés)
{
char[] l = new char[nmbrevaleurTirés];
for (int i = 0; i < nmbrevaleurTirés; i++)
{
l[i] = (char)(new Random().Next(1, 101));
}
return l;
}

use ToChar() method of Convert class.
Convert.ToChar(new Random().Next(1, 101))

You cannot convert an integer larger then 9 into a char because it's considered as 2 chars, i.e. 10 will be considered as 1 and 0.
so I would recommend adding it to an array of strings
(except if your trying to get a random charcode which I dont think is the case, because why till 100?)

Personally, I'd use an int[] array instead
There shouldn't be any problem in storing ints up to 65535 in a char but you will have to cast it back to an int if you don't want it to be weird:
public static void Main()
{
var x = CreationListe(200);
foreach(var c in x)
Console.WriteLine((int)c); //need to cast to int!
}
public static char[] CreationListe(int nmbrevaleurTirés)
{
char[] l = new char[nmbrevaleurTirés];
for (int i = 0; i < nmbrevaleurTirés; i++)
{
l[i] = (char)(new Random().Next(1, 65536));
}
return l;
}
https://dotnetfiddle.net/z5yoBn
If you don't cast it back to int, then you'll get the char at that character index in the unicode table. If you've put 65 into a char, you'll get A when you print it, for example. This is because A is at position 65 in the table:
(ASCII table image posted for brevity's sake)

Getting the sum of all numbers in a character array

I have converted string to char[], but now when I try to get a total of all the numbers in the array, I get a wrong output. The goal is that if the user enters a number as a string e.g - 12, the output should be 3 i.e 1 + 2, another example - 123 should be 1+2+3 = 6.
I am new to coding. My apologies for any inconvienence.
static void Main(string[] args)
{
int sum = 0;
String num = Console.ReadLine();
char[] sep = num.ToCharArray();
for (int i = 0; i < sep.Length; i++)
{
sum += (sep[i]);
}
Console.WriteLine(sum);
Console.ReadLine();
}

You are currently adding ascii values. The ascii value of 1 is 49 and that of 2 Is 50... You need to use int.TryParse to convert from char to int.
int value;
for (int i = 0; i < sep.Length; i++)
{
if (int.TryParse (sep[i].ToString(),out value))
sum += value;
}

If you want to calculate sum of digits, you need to convert each char to int first. Char needs to be converted to string and then parsed into int. Your original code contains implicit conversion, which converts 1 and 2 into 49 and 50 (ASCII), thus the sum ends up being 99.
Try this code instead:
static void Main(string[] args)
{
int sum = 0;
String num = Console.ReadLine();
char[] sep = num.ToCharArray();
for (int i = 0; i < sep.Length; i++)
{
sum += int.Parse(sep[i].ToString());
}
Console.WriteLine(sum);
Console.ReadLine();
}

Just for fun here is a LINQ solution.
var sum = num.Select( c => int.Parse((string)c) ).Sum();
This solution takes advantage of the fact that a string is also an IEnumerable<char> and therefore can be treated as a list of characters.
The Select statement iterates over the characters and converts each one to an integer by supplying a lambda expression (that's the => stuff) that maps each character onto its integer equivalent. The symbol is typically prounced "goes to". You might pronounce the whole expression "C goes to whatever integer can be parsed from it."
Then we call Sum() to convert the resulting list of integers into a numeric sum.

How do I input each value of a string into each separate element of an integer array C#? Windows Form Application

I'm new to all this programming fiasco and I was wondering if there was any way to achieve the goal of what my title suggests?
I have an integer array called "LoyaltyNumber"
- int[] LoyaltyNumber = new int [8]
This array is used to validate a discount code.
I have a string called "NumberBoxInput" which consists of the numbers input by the user through a textbox.
- NumberBoxInput = NumberBox.Text
I was wondering if there was a way to put the whole number into the textbox and then put each of those numbers from the textbox into each separate element of the LoyaltyNumber array (Eg. LoyaltyNumber[0] = the first number input into the textbox)
Eg. If the User input into the Textbox was the number: 46764833
How could I make it that LoyaltyNumber[0] = 4, LoyaltyNumber[1] = 6, LoyaltyNumber[2] = 7 and so on?

As you have mentioned in question regarding user input
If the User input into the Textbox was the number: 46764833
Then try following
String inputSample = "46764833";
var chars = inputSample.ToCharArray().Select(c => c.ToString()).ToArray();
int[] intLoyaltyNumber2 = Array.ConvertAll(chars, int.Parse);
for (int ctr = 0; ctr < chars.Length; ctr++)
Console.WriteLine("{0}: {1}", ctr, chars[ctr]);

I would use the string.Split() method to put the elements of the string into an object, then use a for loop to assign each element to the array.
Example:
//intialize recipient array
int[] numArray = new int[5];
//test string
string nums = "1,2,3,4,5";
//assign each number to its respective element in the 'numList' array, using the ','
//as a separator
string[] numList = nums.Split(',');
//assign each 'numList' element to the recipient array using a 'for' loop
for (int i = 0; i < numArray.Length; i++)
{
//Convert.ToInt32 converts the strings to integers so they can
//be loaded into the recipient array
numArray[i]=Convert.ToInt32(numList[i]);
}
Keep in mind that you would need to have some sort of delimiter separating your numbers in the text box (this can be a comma or a space or anything).
You would also need to be sure that your array is big enough to hold all of the numbers that the user wants to give you.

You can use char[] string.ToCharArray() function, then convert to int like so:
string input = "123456789";
char[] numbersArray = input.ToCharArray();
Console.WriteLine(numbersArray);
//convert to ints ...
Or use Char.IsDigit(char) for validation like so:
string input = "123456789";
int[] numbersArray = new int[numbers.Length];
for (int i = 0; i < numbers.Length; i++)
{
if (Char.IsDigit(numbers[i]))
numbersArray[i] = Int32.Parse(numbers[i].ToString());
Console.Write(numbersArray[i]);
}

Try this, it's a one liner:
String inputSample = "46764833";
int[] sampleArray = Array.ConvertAll<char, int>(inputSample.ToCharArray().Where(c => Char.IsDigit(c)).ToArray(), System.Convert.ToInt32);

Split string into multiple smaller strings

I have a multiline textbox that contains 10 digit mobile numbers separated by comma. I need to achieve string in group of at least 100 mobile numbers.
100 mobile numbers will be separated by 99 comma in total. What i am trying to code is to split the strings containing commas less than 100
public static IEnumerable<string> SplitByLength(this string str, int maxLength)
{
for (int index = 0; index < str.Length; index += maxLength) {
yield return str.Substring(index, Math.Min(maxLength, str.Length - index));
}
}
By using above code, I can achieve 100 numbers as 100 numbers will have 10*100(for mobile number)+99(for comma) text length. But the problem here is user may enter wrong mobile number like 9 digits or even 11 digits.
Can anyone guide me on how can I achieve this.
Thank you in advance.

You could use this extension method to put them into max-100 number groups:
public static IEnumerable<string[]> SplitByLength(this string str, string[] splitBy, StringSplitOptions options, int maxLength = int.MaxValue)
{
var allTokens = str.Split(splitBy, options);
for (int index = 0; index < allTokens.Length; index += maxLength)
{
int length = Math.Min(maxLength, allTokens.Length - index);
string[] part = new string[length];
Array.Copy(allTokens, index, part, 0, length);
yield return part;
}
}
Sample:
string text = string.Join(",", Enumerable.Range(0, 1111).Select(i => "123456789"));
var phoneNumbersIn100Groups = text.SplitByLength(new[] { "," }, StringSplitOptions.None, 100);
foreach (string[] part in phoneNumbersIn100Groups)
{
Assert.IsTrue(part.Length <= 100);
Console.WriteLine(String.Join("|", part));
}

You have a few options,
Put some kind of mask on the input data to prevent the user entering invalid data. In your UI you could then flag the error and prompt the user to reenter correct information. If you go down this route then something like this string[] nums = numbers.Split(','); will be fine.
Alternatively, you could use regex.split or regex.match and match on the pattern. Something like this should work assuming your numbers are in a string with a leading comma or space
Regex regex = new Regex("(\s|,)\d{10},)";
string[] nums = regex.Split(numbers);

This be can resolved with a simple Linq code
public static IEnumerable<string> SplitByLength(this string input, int groupSize)
{
// First split the input to the comma.
// this will give us an array of all single numbers
string[] numbers = input.Split(',');
// Now loop over this array in groupSize blocks
for (int index = 0; index < numbers.Length; index+=groupSize)
{
// Skip numbers from the starting position and
// take the following groupSize numbers,
// join them in a string comma separated and return
yield return string.Join(",", numbers.Skip(index).Take(groupSize));
}
}

Get a range from two integers

string num = db.SelectNums(id);
string[] numArr = num.Split('-').ToArray();
string num contain for an example "48030-48039";
string[] numArr will therefor contain (48030, 48039).
Now I have two elements, a high and low. I now need to get ALL the numbers from 48030 to 48039. The issue is that it has to be string since there will be telephone numbers with leading zeroes now and then.
Thats why I cannot use Enumerable.Range().ToArray() for this.
Any suggestions? The expected result should be 48030, 48031, 48032, ... , 48039

This should work with your leading zero requirement:
string num = db.SelectNums(id);
string[] split = num.Split('-');
long start = long.Parse(split[0]);
long end = long.Parse(split[1]);
bool includeLeadingZero = split[0].StartsWith("0");
List<string> results = new List<string>();
for(int i = start; i <= end; i++)
{
string result = includeLeadingZero ? "0" : "";
result += i.ToString();
results.Add(result);
}
string[] arrayResults = results.ToArray();
A few things to note:
It assumes your input will be 2 valid integers split by a single hyphen
I am giving you a string array result, personally I would prefer to work with a List<int> in the end
If the first number contains a single leading zero, then all results will contain a single leading zero
It uses long to cater for longer numbers, beware that the max number that will parse is 9,223,372,036,854,775,807, you could double this value (not length) by using ulong

Are you saying this?
int[] nums = new int[numArr.Length];
for (int i = 0; i < numArr.Length; i++)
{
nums[i] = Convert.ToInt32(numArr[i]);
}
Array.Sort(nums);
for (int n = nums[0]; n <= nums[nums.Length - 1]; n++)
{
Console.WriteLine(n);
}
here link

I am expecting your string always have valid two integers, so using Parse instead TryParse
string[] strList = "48030-48039".Split('-').ToArray();
var lst = strList.Select(int.Parse).ToList();
var min = lst.OrderBy(l => l).FirstOrDefault();
var max = lst.OrderByDescending(l => l).FirstOrDefault();
var diff = max - min;
//adding 1 here otherwise 48039 will not be there
var rng = Enumerable.Range(min,diff+1);
If you expecting invalid string
var num = 0;
var lst = (from s in strList where int.TryParse(s, out num) select num).ToList();

This is one way to do it:
public static string[] RangeTest()
{
Boolean leadingZero = false;
string num = "048030-48039"; //db.SelectNums(id);
if (num.StartsWith("0"))
leadingZero = true;
int min = int.Parse(num.Split('-').Min());
int count = int.Parse(num.Split('-').Max()) - min;
if (leadingZero)
return Enumerable.Range(min, count).Select(x => "0" + x.ToString()).ToArray();
else
return Enumerable.Range(min, count).Select(x => "" + x.ToString()).ToArray(); ;
}

You can use string.Format to ensure numbers are formatted with leading zeros. That will make the method work with arbitrary number of leading zeros.
private static string CreateRange(string num)
{
var tokens = num.Split('-').Select(s => s.Trim()).ToArray();
// use UInt64 to allow huge numbers
var start = UInt64.Parse(tokens[0]);
var end = UInt64.Parse(tokens[1]);
// if your start number is '000123', this will create
// a format string with 6 zeros ('000000')
var format = new string('0', tokens[0].Length);
// use StringBuilder to make GC happy.
// (if only there was a Enumerable.Range<ulong> overload...)
var sb = new StringBuilder();
for (var i = start; i <= end; i++)
{
// format ensures that your numbers are padded properly
sb.Append(i.ToString(format));
sb.Append(", ");
}
// trim trailing comma after the last element
if (sb.Length >= 2) sb.Length -= 2;
return sb.ToString();
}
Usage example:
// prints 0000012, 0000013, 0000014
Console.WriteLine( CreateRange("0000012-0000014") );

Three significant issues were brought up in comments:
The phone numbers have enough digits to exceed Int32.MaxValue so
converting to int isn't viable.
The phone numbers can have leading zeros (presumeably for some
international calling?)
The possible range of numbers can theoretically exceed the maximum size of an array (which may have memory issues, and I think may not be represented as a string)
As such, you may need to use long instead of int, and I would suggest using deferred execution if needed for very large ranges.
public static IEnumerable<string> EnumeratePhoneNumbers(string fromAndTo)
{
var split = fromAndTo.Split('-');
return EnumeratePhoneNumbers(split[0], split[1]);
}
public static IEnumerable<string> EnumeratePhoneNumbers(string fromString, string toString)
{
long from = long.Parse(fromString);
long to = long.Parse(toString);
int totalNumberLength = fromString.Length;
for (long phoneNumber = from; phoneNumber <= to; phoneNumber++)
{
yield return phoneNumber.ToString().PadLeft(totalNumberLength, '0');
}
}
This assumes that the padded zeros are already included in the lower bound fromString text. It will iterate and yield out numbers as you need them. This can be useful if you're churning out a lot of numbers and don't need to fill up memory with them, or if you just need the first 10 or 100. For example:
var first100Numbers =
EnumeratePhoneNumbers("0018155500-7018155510")
.Take(100)
.ToArray();
Normally that range would produce 7 billion results which cannot be stored in an array, and might run into memory issues (I'm not even sure if it can be stored in a string); by using deferred execution, you only create the 100 needed.
If you do have a small range, you can still join up your results into a string as you desired:
string numberRanges = String.Join(", ", EnumeratePhoneNumbers("0018155500-0018155510"));
And naturally you can put this array creation into your own helper method:
public static string GetPhoneNumbersListing(string fromAndTo)
{
return String.Join(", ", EnumeratePhoneNumbers("0018155500-0018155510"));
}
So your usage would be:
string numberRanges = GetPhoneNumbersListing("0018155500-0018155510");

A complete solution inspired by the answer by #Dan-o:
Inputs:
Start: 48030
End: 48039
Digits: 6
Expected String Output:
048030, 048031, 048032, 048033, 048034, 048035, 048036, 048037, 048038, 048039
Program:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
public class Program
{
public static void Main()
{
int first = 48030;
int last = 48039;
int digits = 6;
Console.WriteLine(CreateRange(first, last, digits));
}
public static string CreateRange(int first, int last, int numDigits)
{
string separator = ", ";
var sb = new StringBuilder();
sb.Append(first.ToString().PadLeft(numDigits, '0'));
foreach (int num in Enumerable.Range(first + 1, last - first))
{
sb.Append(separator + num.ToString().PadLeft(numDigits, '0'));
}
return sb.ToString();
}
}

For Each item In Enumerable.Range(min, count).ToArray()
something = item.PadLeft(5, "0")
Next