Develop Reference

Remove Identical Words from a string array

The goal is to remove a certain prefix word from a string in string array example: ["Market1", "Market2", "Market3"]. The prefix word Market is dominant in string array, so we have to remove Market from string array so the result should be ["1", "2", "3"]. Please take note that the Market prefix word in string could be anything.

Look for the first character that is not identical among all strings and select a substring starting at that position to remove the prefix.
string[] words = new string[] { "Market1", "Market2", "Market3" };
int i = 0;
while (words.All(word => word.Length > i && word[i] == words[0][i])) ++i;
var wordsWithoutPrefixes = words.Select(word => word.Substring(i)).ToArray();

Make a delimited string and then replace all the Market with an empty string and then split the string to an array.
string[] arr = new string[] { "Market1", "Market2", "Market3" };
string[] result = string.Join(".", arr).Replace("Market", "").Split('.');

Loop through each item in the array and for each item chop off the beginning the start matches.
var commonPrefix = "Market";
for (int i = 0; i < arr.length, i++) {
if(arr[i].IndexOf(commonPrefix) == 0) {
arr[i] = arr[i].Substring(commonPrefix.Length);
}
}

You can use LINQ:
string[] myArray = ["Market1", "Market2", "Market3"];
string prefix = myArray[0];
foreach (var s in myArray)
{
while (!s.StartsWith(prefix))
prefix = prefix.Substring(0, prefix.Length - 1);
}
string[] result = myArray
.Select(s => s.Substring(prefix.Length))
.ToArray();

Loop through the array of string and replace the substring containing prefix with an empty substring.
string[] s=new string[]{"Market1","Market2","Market3"};
string prefix="Market";
foreach(var x in s)
{
if(x.Contains(prefix))
{
x=x.Replace(prefix,"");
}
}

string.PadRight() doesn't seem to work in my code

I have a Powershell output to re-format, because formatting gets lost in my StandardOutput.ReadToEnd().There are several blanks to be removed in a line and I want to get the output formatted readable.
Current output in my messageBox looks like
Microsoft.MicrosoftJigsaw All
Microsoft.MicrosoftMahjong All
What I want is
Microsoft.MicrosoftJigsaw All
Microsoft.MicrosoftMahjong All
What am I doing wrong?
My C# knowledge still is basic level only
I found this question here, but maybe I don't understand the answer correctly. The solution doesn't work for me.
Padding a string using PadRight method
This is my current code:
string first = "";
string last = "";
int idx = line.LastIndexOf(" ");
if (idx != -1)
{
first = line.Substring(0, idx).Replace(" ","").PadRight(10, '~');
last = line.Substring(idx + 1);
}
MessageBox.Show(first + last);

String.PadLeft() first parameter defines the length of the padded string, not padding symbol count.
Firstly, you can iterate through all you string, split and save.
Secondly, you should get the longest string length.
Finally, you can format strings to needed format.
var strings = new []
{
"Microsoft.MicrosoftJigsaw All",
"Microsoft.MicrosoftMahjong All"
};
var keyValuePairs = new List<KeyValuePair<string, string>>();
foreach(var item in strings)
{
var parts = item.Split(new [] {" "}, StringSplitOptions.RemoveEmptyEntries);
keyValuePairs.Add(new KeyValuePair<string, string>(parts[0], parts[1]));
}
var longestStringCharCount = keyValuePairs.Select(kv => kv.Key).Max(k => k.Length);
var minSpaceCount = 5; // min space count between parts of the string
var formattedStrings = keyValuePairs.Select(kv => string.Concat(kv.Key.PadRight(longestStringCharCount + minSpaceCount, ' '), kv.Value));
foreach(var item in formattedStrings)
{
Console.WriteLine(item);
}
Result:
Microsoft.MicrosoftJigsaw All
Microsoft.MicrosoftMahjong All

The PadRight(10 is not enough, it is the size of the complete string.
I would probably go for something like:
string[] lines = new[]
{
"Microsoft.MicrosoftJigsaw All",
"Microsoft.MicrosoftMahjong All"
};
// iterate all (example) lines
foreach (var line in lines)
{
// split the string on spaces and remove empty ones
// (so multiple spaces are ignored)
// ofcourse, you must check if the splitted array has atleast 2 elements.
string[] splitted = line.Split(new Char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
// reformat the string, with padding the first string to a total of 40 chars.
var formatted = splitted[0].PadRight(40, ' ') + splitted[1];
// write to anything as output.
Trace.WriteLine(formatted);
}
Will show:
Microsoft.MicrosoftJigsaw All
Microsoft.MicrosoftMahjong All
So you need to determine the maximum length of the first string.

Assuming the length of second part of your string is 10 but you can change it. Try below piece of code:
Function:
private string PrepareStringAfterPadding(string line, int totalLength)
{
int secondPartLength = 10;
int lastIndexOfSpace = line.LastIndexOf(" ");
string firstPart = line.Substring(0, lastIndexOfSpace + 1).Trim().PadRight(totalLength - secondPartLength);
string secondPart = line.Substring(lastIndexOfSpace + 1).Trim().PadLeft(secondPartLength);
return firstPart + secondPart;
}
Calling:
string line1String = PrepareStringAfterPadding("Microsoft.MicrosoftJigsaw All", 40);
string line2String = PrepareStringAfterPadding("Microsoft.MicrosoftMahjong All", 40);
Result:
Microsoft.MicrosoftJigsaw All
Microsoft.MicrosoftMahjong All
Note:
Code is given for demo purpose please customize the totalLength and secondPartLength and calling of the function as per your requirement.

Get first 250 words of a string?

How do I get the first 250 words of a string?

You need to split the string. You can use the overload without parameter(whitespaces are assumed).
IEnumerable<string> words = str.Split().Take(250);
Note that you need to add using System.Linq for Enumerable.Take.
You can use ToList() or ToArray() ro create a new collection from the query or save memory and enumerate it directly:
foreach(string word in words)
Console.WriteLine(word);
Update
Since it seems to be quite popular I'm adding following extension which is more efficient than the Enumerable.Take approach and also returns a collection instead of the (deferred executed) query.
It uses String.Split where white-space characters are assumed to be the delimiters if the separator parameter is null or contains no characters. But the method also allows to pass different delimiters:
public static string[] GetWords(
this string input,
int count = -1,
string[] wordDelimiter = null,
StringSplitOptions options = StringSplitOptions.None)
{
if (string.IsNullOrEmpty(input)) return new string[] { };
if(count < 0)
return input.Split(wordDelimiter, options);
string[] words = input.Split(wordDelimiter, count + 1, options);
if (words.Length <= count)
return words; // not so many words found
// remove last "word" since that contains the rest of the string
Array.Resize(ref words, words.Length - 1);
return words;
}
It can be used easily:
string str = "A B C D E F";
string[] words = str.GetWords(5, null, StringSplitOptions.RemoveEmptyEntries); // A,B,C,D,E

yourString.Split(' ').Take(250);
I guess. You should provide more info.

String.Join(" ", yourstring.Split().Take(250).ToArray())

Addition to Tim answer, this is what you can try
IEnumerable<string> words = str.Split().Take(250);
StringBuilder firstwords = new StringBuilder();
foreach(string s in words)
{
firstwords.Append(s + " ");
}
firstwords.Append("...");
Console.WriteLine(firstwords.ToString());

Try this one:
public string TakeWords(string str,int wordCount)
{
char lastChar='\0';
int spaceFound=0;
var strLen= str.Length;
int i=0;
for(; i<strLen; i++)
{
if(str[i]==' ' && lastChar!=' ')
{
spaceFound++;
}
lastChar=str[i];
if(spaceFound==wordCount)
break;
}
return str.Substring(0,i);
}

It's possible without calling Take().
string[] separatedWords = stringToProcess.Split(new char[] {' '}, 250, StringSplitOptions.RemoveEmptyEntries);
Which also allows splitting based on more than just space " " and therefore fixes occurrences when spaces are incorrectly missing in input.
string[] separatedWords = stringToProcess.Split(new char[] {' ', '.', ',' ':', ';'}, 250, StringSplitOptions.RemoveEmptyEntries);
Use StringSplitOptions.None, if you want empty strings to be returned instead.

Count how many words in each sentence

I'm stuck on how to count how many words are in each sentence, an example of this is: string sentence = "hello how are you. I am good. that's good."
and have it come out like:
//sentence1: 4 words
//sentence2: 3 words
//sentence3: 2 words
I can get the number of sentences
public int GetNoOfWords(string s)
{
return s.Split(new char[] { '.' }, StringSplitOptions.RemoveEmptyEntries).Length;
}
label2.Text = (GetNoOfWords(sentance).ToString());
and i can get the number of words in the whole string
public int CountWord (string text)
{
int count = 0;
for (int i = 0; i < text.Length; i++)
{
if (text[i] != ' ')
{
if ((i + 1) == text.Length)
{
count++;
}
else
{
if(text[i + 1] == ' ')
{
count++;
}
}
}
}
return count;
}
then button1
int words = CountWord(sentance);
label4.Text = (words.ToString());
But I can't count how many words are in each sentence.

Instead of looping over the string as you do in CountWords I would just use;
int words = s.Split(' ').Length;
It's much more clean and simple. You split on white spaces which returns an array of all the words, the length of that array is the number of words in the string.

Why not use Split instead?
var sentences = "hello how are you. I am good. that's good.";
foreach (var sentence in sentences.TrimEnd('.').Split('.'))
Console.WriteLine(sentence.Trim().Split(' ').Count());

If you want number of words in each sentence, you need to
string s = "This is a sentence. Also this counts. This one is also a thing.";
string[] sentences = s.Split(new char[] { '.' }, StringSplitOptions.RemoveEmptyEntries);
foreach(string sentence in sentences)
{
Console.WriteLine(sentence.Split(' ').Length + " words in sentence *" + sentence + "*");
}

Use CountWord on each element of the array returned by s.Split:
string sentence = "hello how are you. I am good. that's good.";
string[] words = sentence.Split(new char[] { '.' }, StringSplitOptions.RemoveEmptyEntries).Length;
for (string sentence in sentences)
{
int noOfWordsInSentence = CountWord(sentence);
}

string text = "hello how are you. I am good. that's good.";
string[] sentences = s.Split(new char[] { '.' }, StringSplitOptions.RemoveEmptyEntries);
IEnumerable<int> wordsPerSentence = sentences.Select(s => s.Trim().Split(' ').Length);

As noted in several answers here, look at String functions like Split, Trim, Replace, etc to get you going. All answers here will solve your simple example, but here are some sentences which they may fail to analyse correctly;
"Hello, how are you?" (no '.' to parse on)
"That apple costs $1.50." (a '.' used as a decimal)
"I like whitespace . "
"Word"

If you only need a count, I'd avoid Split() -- it takes up unnecessary space. Perhaps:
static int WordCount(string s)
{
int wordCount = 0;
for(int i = 0; i < s.Length - 1; i++)
if (Char.IsWhiteSpace(s[i]) && !Char.IsWhiteSpace(s[i + 1]) && i > 0)
wordCount++;
return ++wordCount;
}
public static void Main()
{
Console.WriteLine(WordCount(" H elloWor ld g ")); // prints "4"
}
It counts based on the number of spaces (1 space = 2 words). Consecutive spaces are ignored.

Does your spelling of sentence in:
int words = CountWord(sentance);
have anything to do with it?

Using String Split

I have a text
Category2,"Something with ,comma"
when I split this by ',' it should give me two string
Category2
"Something with ,comma"
but in actual it split string from every comma.
how can I achieve my expected result.
Thanx

Just call variable.Split(new char[] { ',' }, 2). Complete documentation in MSDN.

There are a number of things that you could be wanting to do here so I will address a few:
Split on the first comma
String text = text.Split(new char[] { ',' }, 2);
Split on every comma
String text = text.Split(new char[] {','});
Split on a comma not in "
var result = Regex.Split(samplestring, ",(?=(?:[^']*'[^']*')*[^']*$)");
Last one taken from C# Regex Split

Specify the maximum number of strings you want in the array:
string[] parts = text.Split(new char[] { ',' }, 2);

String.Split works at the simplest, fastest level - so it splits the text on all of the delimiters you pass into it, and it has no concept of special rules like double-quotes.
If you need a CSV parser which understands double-quotes, then you can write your own or there are some excellent open source parsers available - e.g. http://www.codeproject.com/KB/database/CsvReader.aspx - this is one I've used in several projects and recommend.

Try this:
public static class StringExtensions
{
public static IEnumerable<string> SplitToSubstrings(this string str)
{
int startIndex = 0;
bool isInQuotes = false;
for (int index = 0; index < str.Length; index++ )
{
if (str[index] == '\"')
isInQuotes = !isInQuotes;
bool isStartOfNewSubstring = (!isInQuotes && str[index] == ',');
if (isStartOfNewSubstring)
{
yield return str.Substring(startIndex, index - startIndex).Trim();
startIndex = index + 1;
}
}
yield return str.Substring(startIndex).Trim();
}
}
Usage is pretty simple:
foreach(var str in text.SplitToSubstrings())
Console.WriteLine(str);