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I want to remove word Test and Leaf from the specified string beginning only,not from the other side,so string Test_AA_234_6874_Test should be AA_234_6874_Test,But when i use .Replace it will replace word Test from everywhere which i don't want.How to do it
This is the code what i have done it
string st = "Test_AA_234_6874_Test";
st = st.Replace("Test_","");
You could use a regex to do this. The third argument of the regex replace method specifics how many times you want to replace.
string st = "Test_AA_234_6874_Test";
var regex = new Regex("(Test|Leaf)_");
var value = regex.Replace(st, "", 1);
Or if the string to replace only occurs on the start just use ^ which asserts the position at start of the string.
string st = "Test_AA_234_6874_Test";
var regex = new Regex("^(Test|Leaf)_");
var value = regex.Replace(st, "");
If you know that you allways have to remove the first 5 letters you can also use Substring which is more performant.
string st = "Test_AA_234_6874_Test";
var value = st.Substring(5, st.Length - 5);
The simplest way to do this is by using a Regular Expression like so.
using System;
using System.Text.RegularExpressions;
using System.Text;
namespace RegExTest
{
class Program
{
static void Main(string[] args)
{
var input = "Test_AA_234_6874_Test";
var matchText = "Test";
var replacement = String.Empty;
var regex = new Regex("^" + matchText);
var output = regex.Replace(input, replacement);
Console.WriteLine("Converted String: {0}", output);
Console.ReadKey();
}
}
}
The ^ will match text at the beginning of the string.
Consider checking whether the string starts with "Start" and/or ends with "Trim" and decide the end and start positions you'd like to maintain. Then use Substring method to get only the portion you need.
public string Normalize(string input, string prefix, string suffix)
{
// Validation
int length = input.Length;
int startIndex = 0;
if(input.StartsWith(prefix))
{
startIndex = prefix.Length;
length -= prefix.Length;
}
if (input.EndsWith (suffix))
{
length -= suffix.Length;
}
return input.Substring(startIndex, length);
}
Hope this helps.
string wordToRemoveFromBeginning = "Test_";
int index = st.IndexOf(wordToRemoveFromBeginning);
string cleanPath = (index < 0) ? st : st.Remove(index,
wordToRemoveFromBeginning.Length);
Use a regular expression.
var str1 = "Test_AA_234_6874_Test";
var str2 = "Leaf_AA_234_6874_Test";
str1 = Regex.Replace(str1, "^Test", "");
str2 = Regex.Replace(str2, "^Leaf", "");
Regex.Replace parameters are your input string (str1), the pattern you want to match, and what to replace it with, in this case a blank space. The ^ character means look at the start of the string, so something like "MyTest_AAAA_234_6874_Test" would stil return "MyTest_AA_234_6874_Test".
I am gonna use some very simple code here
string str = "Test_AA_234_6874_Test";
string substring = str.Substring(0, 4);
if (substring == "Test" || substring == "Leaf")
{
str= str.Remove(0, 5);
}
I want to trim a string after a special character..
Lets say the string is str="arjunmenon.uking". I want to get the characters after the . and ignore the rest. I.e the resultant string must be restr="uking".
How about:
string foo = str.EverythingAfter('.');
using:
public static string EverythingAfter(this string value, char c)
{
if(string.IsNullOrEmpty(value)) return value;
int idx = value.IndexOf(c);
return idx < 0 ? "" : value.Substring(idx + 1);
}
you can use like
string input = "arjunmenon.uking";
int index = input.LastIndexOf(".");
input = input.Substring(index+1, input.Split('.')[1].ToString().Length );
Use Split function
Try this
string[] restr = str.Split('.');
//restr[0] contains arjunmenon
//restr[1] contains uking
char special = '.';
var restr = str.Substring(str.IndexOf(special) + 1).Trim();
Try Regular Expression Language
using System.IO;
using System;
using System.Text.RegularExpressions;
class Program
{
static void Main()
{
string input = "arjunmenon.uking";
string pattern = #"[a-zA-Z0-9].*\.([a-zA-Z0-9].*)";
foreach (Match match in Regex.Matches(input, pattern))
{
Console.WriteLine(match.Value);
if (match.Groups.Count > 1)
for (int ctr = 1; ctr < match.Groups.Count; ctr++)
Console.WriteLine(" Group {0}: {1}", ctr, match.Groups[ctr].Value);
}
}
}
Result:
arjunmenon.uking
Group 1: uking
Personally, I won't do the split and go for the index[1] in the resulting array, if you already know that your correct stuff is in index[1] in the splitted string, then why don't you just declare a constant with the value you wanted to "extract"?
After you make a Split, just get the last item in the array.
string separator = ".";
string text = "my.string.is.evil";
string[] parts = text.Split(separator);
string restr = parts[parts.length - 1];
The variable restr will be = "evil"
string str = "arjunmenon.uking";
string[] splitStr = str.Split('.');
string restr = splitStr[1];
Not like the methods that uses indexes, this one will allow you not to use the empty string verifications, and the presence of your special caracter, and will not raise exceptions when having empty strings or string that doesn't contain the special caracter:
string str = "arjunmenon.uking";
string restr = str.Split('.').Last();
You may find all the info you need here : http://msdn.microsoft.com/fr-fr/library/b873y76a(v=vs.110).aspx
cheers
I think the simplest way will be this:
string restr, str = "arjunmenon.uking";
restr = str.Substring(str.LastIndexOf('.') + 1);
I want to trim the end off a string if it ends in ", ". That's a comma and a space.
I've tried TrimEnd(', '), but this doesn't work. It has to be only if the string ends this way, so I can't just use .Remove to remove the last two characters. How can I do it?
string txt = " testing, , ";
txt = txt.TrimEnd(',',' '); // txt = "testing"
This uses the overload TrimEnd(params char[] trimChars). You can specify 1 or more chars that will form the set of chars to remove. In this case comma and space.
This should work:
string s = "Bar, ";
if (s.EndsWith(", "))
s = s.Substring(0, s.Length - 2);
EDIT
Come to think of it, this would make a nice extension method:
public static String RemoveSuffix(this string value, string suffix)
{
if (value.EndsWith(suffix))
return value.Substring(0, value.Length - suffix.Length);
return value;
}
Try this:
string someText = "some text, ";
char[] charsToTrim = { ',', ' ' };
someText = someText.TrimEnd(charsToTrim);
Works for me.
The catch is that mystring.Trim(',') will only work if you reassign it to the string itself like this:
mystring = mystring.Trim(',')
"value, ".Trim().TrimEnd(",") should also work.
if (model != null && ModelState.IsValid)
{
var categoryCreate = new Categories
{
CategoryName = model.CategoryName.TrimStart().TrimEnd(),
Description = model.Description.TrimStart().TrimEnd()
};
_CategoriesService.Create(categoryCreate);
}
TrimStart().TrimEnd() == Left Trim and Right Trim
How can the first letter in a text be set to capital?
Example:
it is a text. = It is a text.
public static string ToUpperFirstLetter(this string source)
{
if (string.IsNullOrEmpty(source))
return string.Empty;
// convert to char array of the string
char[] letters = source.ToCharArray();
// upper case the first char
letters[0] = char.ToUpper(letters[0]);
// return the array made of the new char array
return new string(letters);
}
It'll be something like this:
// precondition: before must not be an empty string
String after = before.Substring(0, 1).ToUpper() + before.Substring(1);
polygenelubricants' answer is fine for most cases, but you potentially need to think about cultural issues. Do you want this capitalized in a culture-invariant way, in the current culture, or a specific culture? It can make a big difference in Turkey, for example. So you may want to consider:
CultureInfo culture = ...;
text = char.ToUpper(text[0], culture) + text.Substring(1);
or if you prefer methods on String:
CultureInfo culture = ...;
text = text.Substring(0, 1).ToUpper(culture) + text.Substring(1);
where culture might be CultureInfo.InvariantCulture, or the current culture etc.
For more on this problem, see the Turkey Test.
If you are using C# then try this code:
Microsoft.VisualBasic.StrConv(sourceString, Microsoft.VisualBasic.vbProperCase)
I use this variant:
private string FirstLetterCapital(string str)
{
return Char.ToUpper(str[0]) + str.Remove(0, 1);
}
If you are sure that str variable is valid (never an empty-string or null), try:
str = Char.ToUpper(str[0]) + str[1..];
Unlike the other solutions that use Substring, this one does not do additional string allocations. This example basically concatenates char with ReadOnlySpan<char>.
I realize this is an old post, but I recently had this problem and solved it with the following method.
private string capSentences(string str)
{
string s = "";
if (str[str.Length - 1] == '.')
str = str.Remove(str.Length - 1, 1);
char[] delim = { '.' };
string[] tokens = str.Split(delim);
for (int i = 0; i < tokens.Length; i++)
{
tokens[i] = tokens[i].Trim();
tokens[i] = char.ToUpper(tokens[i][0]) + tokens[i].Substring(1);
s += tokens[i] + ". ";
}
return s;
}
In the sample below clicking on the button executes this simple code outBox.Text = capSentences(inBox.Text.Trim()); which pulls the text from the upper box and puts it in the lower box after the above method runs on it.
Take the first letter out of the word and then extract it to the other string.
strFirstLetter = strWord.Substring(0, 1).ToUpper();
strFullWord = strFirstLetter + strWord.Substring(1);
text = new String(
new [] { char.ToUpper(text.First()) }
.Concat(text.Skip(1))
.ToArray()
);
this functions makes capital the first letter of all words in a string
public static string FormatSentence(string source)
{
var words = source.Split(' ').Select(t => t.ToCharArray()).ToList();
words.ForEach(t =>
{
for (int i = 0; i < t.Length; i++)
{
t[i] = i.Equals(0) ? char.ToUpper(t[i]) : char.ToLower(t[i]);
}
});
return string.Join(" ", words.Select(t => new string(t)));;
}
string str = "it is a text";
// first use the .Trim() method to get rid of all the unnecessary space at the begining and the end for exemple (" This string ".Trim() is gonna output "This string").
str = str.Trim();
char theFirstLetter = str[0]; // this line is to take the first letter of the string at index 0.
theFirstLetter.ToUpper(); // .ToTupper() methode to uppercase the firstletter.
str = theFirstLetter + str.substring(1); // we add the first letter that we uppercased and add the rest of the string by using the str.substring(1) (str.substring(1) to skip the first letter at index 0 and only print the letters from the index 1 to the last index.)
Console.WriteLine(str); // now it should output "It is a text"
static String UppercaseWords(String BadName)
{
String FullName = "";
if (BadName != null)
{
String[] FullBadName = BadName.Split(' ');
foreach (string Name in FullBadName)
{
String SmallName = "";
if (Name.Length > 1)
{
SmallName = char.ToUpper(Name[0]) + Name.Substring(1).ToLower();
}
else
{
SmallName = Name.ToUpper();
}
FullName = FullName + " " + SmallName;
}
}
FullName = FullName.Trim();
FullName = FullName.TrimEnd();
FullName = FullName.TrimStart();
return FullName;
}
string Input = " it is my text";
Input = Input.TrimStart();
//Create a char array
char[] Letters = Input.ToCharArray();
//Make first letter a capital one
string First = char.ToUpper(Letters[0]).ToString();
//Concatenate
string Output = string.Concat(First,Input.Substring(1));
Try this code snippet:
char nm[] = "this is a test";
if(char.IsLower(nm[0])) nm[0] = char.ToUpper(nm[0]);
//print result: This is a test
How can I replace multiple spaces in a string with only one space in C#?
Example:
1 2 3 4 5
would be:
1 2 3 4 5
I like to use:
myString = Regex.Replace(myString, #"\s+", " ");
Since it will catch runs of any kind of whitespace (e.g. tabs, newlines, etc.) and replace them with a single space.
string sentence = "This is a sentence with multiple spaces";
RegexOptions options = RegexOptions.None;
Regex regex = new Regex("[ ]{2,}", options);
sentence = regex.Replace(sentence, " ");
string xyz = "1 2 3 4 5";
xyz = string.Join( " ", xyz.Split( new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries ));
I think Matt's answer is the best, but I don't believe it's quite right. If you want to replace newlines, you must use:
myString = Regex.Replace(myString, #"\s+", " ", RegexOptions.Multiline);
Another approach which uses LINQ:
var list = str.Split(' ').Where(s => !string.IsNullOrWhiteSpace(s));
str = string.Join(" ", list);
It's much simpler than all that:
while(str.Contains(" ")) str = str.Replace(" ", " ");
Regex can be rather slow even with simple tasks. This creates an extension method that can be used off of any string.
public static class StringExtension
{
public static String ReduceWhitespace(this String value)
{
var newString = new StringBuilder();
bool previousIsWhitespace = false;
for (int i = 0; i < value.Length; i++)
{
if (Char.IsWhiteSpace(value[i]))
{
if (previousIsWhitespace)
{
continue;
}
previousIsWhitespace = true;
}
else
{
previousIsWhitespace = false;
}
newString.Append(value[i]);
}
return newString.ToString();
}
}
It would be used as such:
string testValue = "This contains too much whitespace."
testValue = testValue.ReduceWhitespace();
// testValue = "This contains too much whitespace."
myString = Regex.Replace(myString, " {2,}", " ");
For those, who don't like Regex, here is a method that uses the StringBuilder:
public static string FilterWhiteSpaces(string input)
{
if (input == null)
return string.Empty;
StringBuilder stringBuilder = new StringBuilder(input.Length);
for (int i = 0; i < input.Length; i++)
{
char c = input[i];
if (i == 0 || c != ' ' || (c == ' ' && input[i - 1] != ' '))
stringBuilder.Append(c);
}
return stringBuilder.ToString();
}
In my tests, this method was 16 times faster on average with a very large set of small-to-medium sized strings, compared to a static compiled Regex. Compared to a non-compiled or non-static Regex, this should be even faster.
Keep in mind, that it does not remove leading or trailing spaces, only multiple occurrences of such.
This is a shorter version, which should only be used if you are only doing this once, as it creates a new instance of the Regex class every time it is called.
temp = new Regex(" {2,}").Replace(temp, " ");
If you are not too acquainted with regular expressions, here's a short explanation:
The {2,} makes the regex search for the character preceding it, and finds substrings between 2 and unlimited times.
The .Replace(temp, " ") replaces all matches in the string temp with a space.
If you want to use this multiple times, here is a better option, as it creates the regex IL at compile time:
Regex singleSpacify = new Regex(" {2,}", RegexOptions.Compiled);
temp = singleSpacify.Replace(temp, " ");
You can simply do this in one line solution!
string s = "welcome to london";
s.Replace(" ", "()").Replace(")(", "").Replace("()", " ");
You can choose other brackets (or even other characters) if you like.
no Regex, no Linq... removes leading and trailing spaces as well as reducing any embedded multiple space segments to one space
string myString = " 0 1 2 3 4 5 ";
myString = string.Join(" ", myString.Split(new char[] { ' ' },
StringSplitOptions.RemoveEmptyEntries));
result:"0 1 2 3 4 5"
// Mysample string
string str ="hi you are a demo";
//Split the words based on white sapce
var demo= str .Split(' ').Where(s => !string.IsNullOrWhiteSpace(s));
//Join the values back and add a single space in between
str = string.Join(" ", demo);
// output: string str ="hi you are a demo";
Consolodating other answers, per Joel, and hopefully improving slightly as I go:
You can do this with Regex.Replace():
string s = Regex.Replace (
" 1 2 4 5",
#"[ ]{2,}",
" "
);
Or with String.Split():
static class StringExtensions
{
public static string Join(this IList<string> value, string separator)
{
return string.Join(separator, value.ToArray());
}
}
//...
string s = " 1 2 4 5".Split (
" ".ToCharArray(),
StringSplitOptions.RemoveEmptyEntries
).Join (" ");
I just wrote a new Join that I like, so I thought I'd re-answer, with it:
public static string Join<T>(this IEnumerable<T> source, string separator)
{
return string.Join(separator, source.Select(e => e.ToString()).ToArray());
}
One of the cool things about this is that it work with collections that aren't strings, by calling ToString() on the elements. Usage is still the same:
//...
string s = " 1 2 4 5".Split (
" ".ToCharArray(),
StringSplitOptions.RemoveEmptyEntries
).Join (" ");
Many answers are providing the right output but for those looking for the best performances, I did improve Nolanar's answer (which was the best answer for performance) by about 10%.
public static string MergeSpaces(this string str)
{
if (str == null)
{
return null;
}
else
{
StringBuilder stringBuilder = new StringBuilder(str.Length);
int i = 0;
foreach (char c in str)
{
if (c != ' ' || i == 0 || str[i - 1] != ' ')
stringBuilder.Append(c);
i++;
}
return stringBuilder.ToString();
}
}
Use the regex pattern
[ ]+ #only space
var text = Regex.Replace(inputString, #"[ ]+", " ");
I know this is pretty old, but ran across this while trying to accomplish almost the same thing. Found this solution in RegEx Buddy. This pattern will replace all double spaces with single spaces and also trim leading and trailing spaces.
pattern: (?m:^ +| +$|( ){2,})
replacement: $1
Its a little difficult to read since we're dealing with empty space, so here it is again with the "spaces" replaced with a "_".
pattern: (?m:^_+|_+$|(_){2,}) <-- don't use this, just for illustration.
The "(?m:" construct enables the "multi-line" option. I generally like to include whatever options I can within the pattern itself so it is more self contained.
I can remove whitespaces with this
while word.contains(" ") //double space
word = word.Replace(" "," "); //replace double space by single space.
word = word.trim(); //to remove single whitespces from start & end.
Without using regular expressions:
while (myString.IndexOf(" ", StringComparison.CurrentCulture) != -1)
{
myString = myString.Replace(" ", " ");
}
OK to use on short strings, but will perform badly on long strings with lots of spaces.
try this method
private string removeNestedWhitespaces(char[] st)
{
StringBuilder sb = new StringBuilder();
int indx = 0, length = st.Length;
while (indx < length)
{
sb.Append(st[indx]);
indx++;
while (indx < length && st[indx] == ' ')
indx++;
if(sb.Length > 1 && sb[0] != ' ')
sb.Append(' ');
}
return sb.ToString();
}
use it like this:
string test = removeNestedWhitespaces("1 2 3 4 5".toCharArray());
Here is a slight modification on Nolonar original answer.
Checking if the character is not just a space, but any whitespace, use this:
It will replace any multiple whitespace character with a single space.
public static string FilterWhiteSpaces(string input)
{
if (input == null)
return string.Empty;
var stringBuilder = new StringBuilder(input.Length);
for (int i = 0; i < input.Length; i++)
{
char c = input[i];
if (i == 0 || !char.IsWhiteSpace(c) || (char.IsWhiteSpace(c) &&
!char.IsWhiteSpace(strValue[i - 1])))
stringBuilder.Append(c);
}
return stringBuilder.ToString();
}
How about going rogue?
public static string MinimizeWhiteSpace(
this string _this)
{
if (_this != null)
{
var returned = new StringBuilder();
var inWhiteSpace = false;
var length = _this.Length;
for (int i = 0; i < length; i++)
{
var character = _this[i];
if (char.IsWhiteSpace(character))
{
if (!inWhiteSpace)
{
inWhiteSpace = true;
returned.Append(' ');
}
}
else
{
inWhiteSpace = false;
returned.Append(character);
}
}
return returned.ToString();
}
else
{
return null;
}
}
Mix of StringBuilder and Enumerable.Aggregate() as extension method for strings:
using System;
using System.Linq;
using System.Text;
public static class StringExtension
{
public static string CondenseSpaces(this string s)
{
return s.Aggregate(new StringBuilder(), (acc, c) =>
{
if (c != ' ' || acc.Length == 0 || acc[acc.Length - 1] != ' ')
acc.Append(c);
return acc;
}).ToString();
}
public static void Main()
{
const string input = " (five leading spaces) (five internal spaces) (five trailing spaces) ";
Console.WriteLine(" Input: \"{0}\"", input);
Console.WriteLine("Output: \"{0}\"", StringExtension.CondenseSpaces(input));
}
}
Executing this program produces the following output:
Input: " (five leading spaces) (five internal spaces) (five trailing spaces) "
Output: " (five leading spaces) (five internal spaces) (five trailing spaces) "
Old skool:
string oldText = " 1 2 3 4 5 ";
string newText = oldText
.Replace(" ", " " + (char)22 )
.Replace( (char)22 + " ", "" )
.Replace( (char)22 + "", "" );
Assert.That( newText, Is.EqualTo( " 1 2 3 4 5 " ) );
You can create a StringsExtensions file with a method like RemoveDoubleSpaces().
StringsExtensions.cs
public static string RemoveDoubleSpaces(this string value)
{
Regex regex = new Regex("[ ]{2,}", RegexOptions.None);
value = regex.Replace(value, " ");
// this removes space at the end of the value (like "demo ")
// and space at the start of the value (like " hi")
value = value.Trim(' ');
return value;
}
And then you can use it like this:
string stringInput =" hi here is a demo ";
string stringCleaned = stringInput.RemoveDoubleSpaces();
I looked over proposed solutions, could not find the one that would handle mix of white space characters acceptable for my case, for example:
Regex.Replace(input, #"\s+", " ") - it will eat your line breaks, if they are mixed with spaces, for example \n \n sequence will be replaced with
Regex.Replace(source, #"(\s)\s+", "$1") - it will depend on whitespace first character, meaning that it again might eat your line breaks
Regex.Replace(source, #"[ ]{2,}", " ") - it won't work correctly when there's mix of whitespace characters - for example "\t \t "
Probably not perfect, but quick solution for me was:
Regex.Replace(input, #"\s+",
(match) => match.Value.IndexOf('\n') > -1 ? "\n" : " ", RegexOptions.Multiline)
Idea is - line break wins over the spaces and tabs.
This won't handle windows line breaks correctly, but it would be easy to adjust to work with that too, don't know regex that well - may be it is possible to fit into single pattern.
The following code remove all the multiple spaces into a single space
public string RemoveMultipleSpacesToSingle(string str)
{
string text = str;
do
{
//text = text.Replace(" ", " ");
text = Regex.Replace(text, #"\s+", " ");
} while (text.Contains(" "));
return text;
}