My apologies if I didn't explain it clear the first time. I have edited my explanation further in bold below.
In the program below user enters a word and then enters a letter which the user would like to replace with any character. For instance, user enter's a word "Hello" and the replacement letter is "l" with "$". So "Hello" will become "He$$o". First, the goal is to find the location of "l" (example - 2,3) and then replace the element in that specific location.
I started by finding the location of "l" and storing it in a findIndex array. Every time I run the program I get "22222" stored in findIndex[] array. At this point, I am not even sure if I am even applying the right logic. Any advice will be appreciated! Please don't use LINQ.
public static void RemoveSpecifiedCharacters()
{
Console.WriteLine("\nWrite a word/sentence: ");
string myString = Console.ReadLine();
Console.Write("Type the character you would like to replace: ");
string myCharacter = Console.ReadLine();
int[] findIndex = new int[myString.Length];
for (int i = 0; i < myString.Length; i++)
{
findIndex[i] = myString.IndexOf(myCharacter, 0);
}
for (int i = 0; i < findIndex.Length; i++)
{
Console.Write(findIndex[i]);
}
}
This is probably what you want :
public static void RemoveSpecifiedCharacters()
{
Console.WriteLine("\nWrite a word/sentence: ");
string myString = Console.ReadLine();
Console.Write("Type the character you would like to replace: ");
string myCharacter = Console.ReadLine();
List<int> findIndex = new List<int>();
int offs = 0;
while (offs < myString.Length)
{
offs = myString.IndexOf(myCharacter, offs);;
if (offs == -1)
break;
findIndex.Add(offs);
offs++;
}
for (int i = 0; i < findIndex.Count; i++)
{
Console.Write(findIndex[i]);
}
}
Set an initial offset to the start of the string, try to find index of required character if not found exit, otherwise store the location & increment the offset so the next loop starts after the found position. Then keep looping.
As you do not know how many characters will be found, then a list is better than an array to store the results. It can always be converted to an array with .ToArray() afterwards.
Below should serve the purpose :
var str = "Hello";
var replaced = str.Replace('l', '$');
Even though it's easier to use String.Replace, I just want to give you an explanation why you are getting [2,2,2,2,2] array.
Firstly, IndexOf method returns index of character's first occurence, starting from 0.
Secondly, you are using method overload IndexOf(myCharacter, 0) which "says" that character search should be done always from the start of the string.
To circumvent the issue, you should use IndexOf(myCharacter, i, 1) instead to set the search to start from i-th character, not the start of string.
I guess a simple solution would be to split the string into a character array and then do the comparison?
For example something like:
Console.WriteLine("\nWrite a word/sentence: ");
char[] myString = Console.ReadLine().ToCharArray();
Console.Write("Type the character you would like to replace: ");
char myCharacter = Console.ReadLine().ToCharArray()[0];
int[] findIndex = new int[myString.Length];
int indexCount = 0;
for (int i = 0; i < myString.Length; i++)
{
if (myString[i] == myCharacter)
findIndex[indexCount++] = i;
}
for (int i = 0; i < indexCount; i++)
{
Console.Write(findIndex[i]);
}
Related
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())+"}");
}
I do not understand why this code prints the contents of the array twice.
static void Main(string[] args)
{
Int64 userlength;
Int64 userlengthcounter;
String unencrypted;
char current;
start:
Console.WriteLine("Please enter how many characters the string you want encrypyted to be:");
userlength = Convert.ToInt64(Console.ReadLine());
Console.WriteLine("Please enter the string you want to be encrypted:");
unencrypted = Console.ReadLine();
int[] first = new int[userlength];
int[] second = new int[userlength];
if (userlength != unencrypted.Length)
{
Console.WriteLine("The string you entered was not the same length as the number of characters you specified");
goto start;
}
for (int i = 0; i < userlength; i++)
{
Console.WriteLine(unencrypted[i]);
current = unencrypted[i];
first[i] = current;
}
foreach (char item in first)
{
Console.WriteLine(item.ToString());
}
Console.ReadLine();
}
For example entering abcd would return abcdabcd and i don't understand why. Any help would be appreciated thanks.
It's because you have two loops, first you print each character in unencrypted in the for loop and store the chars in first array.
Then you loop over the array and print the chars again with foreach.
Additional Note: Using goto is almost always a bad idea because it makes your code hard to follow and unreadable. Because you have to manually track where the code jumps.
You can do the same thing with a do-while loop instead.
do {
Console.WriteLine("Please enter how many characters the string you want encrypyted to be:");
userlength = Convert.ToInt64(Console.ReadLine());
Console.WriteLine("Please enter the string you want to be encrypted:");
unencrypted = Console.ReadLine();
int[] first = new int[userlength];
int[] second = new int[userlength];
if (userlength != unencrypted.Length)
{
Console.WriteLine("The string you entered was not the same length as the number of characters you specified");
}
} while(userlength != unencrypted.Length);
you specifically build "first" then you print it in foreach, basically displaying the same content twice:
for (int i = 0; i < userlength; i++)
{
Console.WriteLine(unencrypted[i]);
current = unencrypted[i];
first[i] = current;
}
foreach (char item in first)
{
Console.WriteLine(item.ToString());
}
I need to capitalize everything before the second - from the beginning of the string in .NET. What is the best way to do this? The string before the second dash can be anything. I need a new single string once this is complete.
Before
Tt-Fga - Louisville - Kentucky
After
TT-FGA - Louisville - Kentucky
This should get the job done for your specific case:
public static string ToUpperUntilSecondHyphen(string text)
{
int index = text.IndexOf('-', text.IndexOf('-') + 1);
return text.Substring(0, index).ToUpper() + text.Substring(index);
}
A more generalized method could look something like this:
public static string ToUpperUntilNthOccurrenceOfChar(string text, char c, int occurrences)
{
if (occurrences > text.Count(x => x == c))
{
return text.ToUpper();
}
int index = 0;
for (int i = 0; i < occurrences; i++, index++)
{
index = text.IndexOf(c, index);
}
return text.Substring(0, index).ToUpper() + text.Substring(index);
}
Identify the location of the hyphen with IndexOf. You'll have to use this function twice so that you can find the first hyphen, and then the second one.
Construct the substring that only contains the characters up to that with Substring. Construct the substring that contains all the remaining characters as well.
Upper case the first string with ToUpper.
Concatenate with the + operator.
(.*?-.*)(?=-)
You can use replace here.Replace with $1.upper() or something which is available in c#.
See
http://regex101.com/r/yR3mM3/50
I went ahead and did this. If there is a better answer let me know.
var parts = #event.EventParent.Name.Split(new[] {'-'}, StringSplitOptions.RemoveEmptyEntries);
for (int i = 0; i < parts.Length; i++)
{
if (i >= 2)
break;
parts[i] = parts[i].ToUpper();
}
#event.EventParent.Name = string.Join("-", parts);
Hello I'm try to remove special characters from user inputs.
public void fd()
{
string output = "";
string input = Console.ReadLine();
char[] charArray = input.ToCharArray();
foreach (var item in charArray)
{
if (!Char.IsLetterOrDigit(item))
{
\\\CODE HERE }
}
output = new string(trimmedChars);
Console.WriteLine(output);
}
At the end I'm turning it back to a string. My code only removes one special character in the string. Does anyone have any suggestions on a easier way instead
You have a nice implementation, just consider using next code, which is only a bit shorter, but has a little bit higher abstractions
var input = " th#ere's! ";
Func<char, bool> isSpecialChar = ch => !char.IsLetter(ch) && !char.IsDigit(ch);
for (int i = 1; i < input.Length - 1; i++)
{
//if current character is a special symbol
if(isSpecialChar(input[i]))
{
//if previous or next character are special symbols
if(isSpecialChar(input[i-1]) || isSpecialChar(input[i+1]))
{
//remove that character
input = input.Remove(i, 1);
//decrease counter, since we removed one char
i--;
}
}
}
Console.WriteLine(input); //prints " th#ere's "
A new string would be created each time you would call Remove. Use a StringBuilder for a more memory-performant solution.
The problem with your code is that you are taking the data from charArray and putting the result in trimmedChars for each change that you make, so each change will ignore all previous changes and work with the original. At the end you only have the last change.
Another problem with the code is that you are using IndexOf to get the index of a character, but that will get the index of the first occurance of that character, not the index where you got that character. For example when you are at the second ! in the string "foo!bar!" you will get the index of the first one.
You don't need to turn the string into an array to work with the characters in the string. You can just loop through the index of the characters in the string.
Note that you should also check the value of the index when you are looking at the characters before and after, so that you don't try to look at characters that are outside the string.
public void fd() {
string input = Console.ReadLine();
int index = 0;
while (index < input.Length) {
if (!Char.IsLetterOrDigit(input, index) && ((index == 0 || !Char.IsLetterOrDigit(input, index - 1)) || (index == input.Length - 1 || !Char.IsLetterOrDigit(input, index + 1)))) {
input = input.Remove(index, 1);
} else {
index++;
}
}
Console.WriteLine(input);
}
Been awhile since I've hit on C#, but a reg ex might be helpful
string input = string.Format("{0}! ", Console.ReadLine());
Regex rgx = new Regex("(?i:[^a-z]?)[.](?i:[^a-z]?)");
string output = rgx.Replace(input, "$1$2");
The regex looks for a character with a non-alpha character on left or right and replaces it with nothing.
i have a string like this:
some_string = "A simple demo of SMS text messaging.\r\n+CMGW: 3216\r\n\r\nOK\r\n\"
im coming from vb.net and i need to know in c#, if i know the position of CMGW, how do i get "3216" out of there?
i know that my start should be the position of CMGW + 6, but how do i make it stop as soon as it finds "\r" ??
again, my end result should be 3216
thank you!
Find the index of \r from the start of where you're interested in, and use the Substring overload which takes a length:
// Production code: add validation here.
// (Check for each index being -1, meaning "not found")
int cmgwIndex = text.IndexOf("CMGW: ");
// Just a helper variable; makes the code below slightly prettier
int startIndex = cmgwIndex + 6;
int crIndex = text.IndexOf("\r", startIndex);
string middlePart = text.Substring(startIndex, crIndex - startIndex);
If you know the position of 3216 then you can just do the following
string inner = some_string.SubString(positionOfCmgw+6,4);
This code will take the substring of some_string starting at the given position and only taking 4 characters.
If you want to be more general you could do the following
int start = positionOfCmgw+6;
int endIndex = some_string.IndexOf('\r', start);
int length = endIndex - start;
string inner = some_string.SubString(start, length);
One option would be to start from your known index and read characters until you hit a non-numeric value. Not the most robust solution, but it will work if you know your input's always going to look like this (i.e., no decimal points or other non-numeric characters within the numeric part of the string).
Something like this:
public static int GetNumberAtIndex(this string text, int index)
{
if (index < 0 || index >= text.Length)
throw new ArgumentOutOfRangeException("index");
var sb = new StringBuilder();
for (int i = index; i < text.Length; ++i)
{
char c = text[i];
if (!char.IsDigit(c))
break;
sb.Append(c);
}
if (sb.Length > 0)
return int.Parse(sb.ToString());
else
throw new ArgumentException("Unable to read number at the specified index.");
}
Usage in your case would look like:
string some_string = #"A simple demo of SMS text messaging.\r\n+CMGW: 3216\r\n...";
int index = some_string.IndexOf("CMGW") + 6;
int value = some_string.GetNumberAtIndex(index);
Console.WriteLine(value);
Output:
3216
If you're looking to extract the number portion of 'CMGW: 3216' then a more reliable method would be to use regular expressions. That way you can look for the entire pattern, and not just the header.
var some_string = "A simple demo of SMS text messaging.\r\n+CMGW: 3216\r\n\r\nOK\r\n";
var match = Regex.Match(some_string, #"CMGW\: (?<number>[0-9]+)", RegexOptions.Multiline);
var number = match.Groups["number"].Value;
More general, if you don't know the start position of CMGW but the structure remains as before.
String s;
char[] separators = {'\r'};
var parts = s.Split(separators);
parts.Where(part => part.Contains("CMGW")).Single().Reverse().TakeWhile(c => c != ' ').Reverse();