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How can I remove all white space from the beginning and end of a string?
Like so:
"hello" returns "hello"
"hello " returns "hello"
" hello " returns "hello"
" hello world " returns "hello world"
String.Trim() returns a string which equals the input string with all white-spaces trimmed from start and end:
" A String ".Trim() -> "A String"
String.TrimStart() returns a string with white-spaces trimmed from the start:
" A String ".TrimStart() -> "A String "
String.TrimEnd() returns a string with white-spaces trimmed from the end:
" A String ".TrimEnd() -> " A String"
None of the methods modify the original string object.
(In some implementations at least, if there are no white-spaces to be trimmed, you get back the same string object you started with:
csharp> string a = "a";
csharp> string trimmed = a.Trim();
csharp> (object) a == (object) trimmed;
returns true
I don't know whether this is guaranteed by the language.)
take a look at Trim() which returns a new string with whitespace removed from the beginning and end of the string it is called on.
string a = " Hello ";
string trimmed = a.Trim();
trimmed is now "Hello"
use the String.Trim() function.
string foo = " hello ";
string bar = foo.Trim();
Console.WriteLine(bar); // writes "hello"
Use String.Trim method.
String.Trim() removes all whitespace from the beginning and end of a string.
To remove whitespace inside a string, or normalize whitespace, use a Regular Expression.
Trim()
Removes all leading and trailing white-space characters from the current string.
Trim(Char)
Removes all leading and trailing instances of a character from the current string.
Trim(Char[]) Removes all leading and trailing occurrences of a set of characters specified in an array from the current string.
Look at the following example that I quoted from Microsoft's documentation page.
char[] charsToTrim = { '*', ' ', '\''};
string banner = "*** Much Ado About Nothing ***";
string result = banner.Trim(charsToTrim);
Console.WriteLine("Trimmmed\n {0}\nto\n '{1}'", banner, result);
// The example displays the following output:
// Trimmmed
// *** Much Ado About Nothing ***
// to
// 'Much Ado About Nothing'
I have a need to get rid of all line breaks that appear in my strings (coming from db).
I do it using code below:
value.Replace("\r\n", "").Replace("\n", "").Replace("\r", "")
I can see that there's at least one character acting like line ending that survived it. The char code is 8232.
It's very lame of me, but I must say this is the first time I have a pleasure of seeing this char. It's obvious that I can just replace this char directly, but I was thinking about extending my current approach (based on replacing combinations of "\r" and "\n") to something much more solid, so it would not only include the '8232' char but also all others not-found-by-me yet.
Do you have a bullet-proof approach for such a problem?
EDIT#1:
It seems to me that there are several possible solutions:
use Regex.Replace
remove all chars if it's IsSeparator or IsControl
replace with " " if it's IsWhiteSpace
create a list of all possible line endings ( "\r\n", "\r", "\n",LF ,VT, FF, CR, CR+LF, NEL, LS, PS) and just replace them with empty string. It's a lot of replaces.
I would say that the best results will be after applying 1st and 4th approaches but I cannot decide which will be faster. Which one do you think is the most complete one?
EDIT#2
I posted anwer below.
Below is the extension method solving my problem. LineSeparator and ParagraphEnding can be of course defined somewhere else, as static values etc.
public static string RemoveLineEndings(this string value)
{
if(String.IsNullOrEmpty(value))
{
return value;
}
string lineSeparator = ((char) 0x2028).ToString();
string paragraphSeparator = ((char)0x2029).ToString();
return value.Replace("\r\n", string.Empty)
.Replace("\n", string.Empty)
.Replace("\r", string.Empty)
.Replace(lineSeparator, string.Empty)
.Replace(paragraphSeparator, string.Empty);
}
According to wikipedia, there are numerous line terminators you may need to handle (including this one you mention).
LF: Line Feed, U+000A
VT: Vertical Tab, U+000B
FF: Form Feed, U+000C
CR: Carriage Return, U+000D
CR+LF: CR (U+000D) followed by LF (U+000A)
NEL: Next Line, U+0085
LS: Line Separator, U+2028
PS: Paragraph Separator, U+2029
8232 (0x2028) and 8233 (0x2029) are the only other ones you might want to eliminate. See the documentation for char.IsSeparator.
Props to Yossarian on this one, I think he's right. Replace all whitespace with a single space:
data = Regex.Replace(data, #"\s+", " ");
I'd recommend removing ALL the whitespace (char.IsWhitespace), and replacing it with single space.. IsWhiteSpace takes care of all weird unicode whitespaces.
This is my first attempt at this, but I think this will do what you want....
var controlChars = from c in value.ToCharArray() where Char.IsControl(c) select c;
foreach (char c in controlChars)
value = value.Replace(c.ToString(), "");
Also, see this link for details on other methods you can use: Char Methods
Have you tried string.Replace(Environment.NewLine, "") ? That usually gets a lot of them for me.
Check out this link: http://msdn.microsoft.com/en-us/library/844skk0h.aspx
You wil lhave to play around and build a REGEX expression that works for you. But here's the skeleton...
static void Main(string[] args)
{
StringBuilder txt = new StringBuilder();
txt.Append("Hello \n\n\r\t\t");
txt.Append( Convert.ToChar(8232));
System.Console.WriteLine("Original: <" + txt.ToString() + ">");
System.Console.WriteLine("Cleaned: <" + CleanInput(txt.ToString()) + ">");
System.Console.Read();
}
static string CleanInput(string strIn)
{
// Replace invalid characters with empty strings.
return Regex.Replace(strIn, #"[^\w\.#-]", "");
}
Assuming that 8232 is unicode, you can do this:
value.Replace("\u2028", string.Empty);
personally i'd go with
public static String RemoveLineEndings(this String text)
{
StringBuilder newText = new StringBuilder();
for (int i = 0; i < text.Length; i++)
{
if (!char.IsControl(text, i))
newText.Append(text[i]);
}
return newText.ToString();
}
If you've a string say "theString" then
use the method Replace and give it the arguments shown below:
theString = theString.Replace(System.Environment.NewLine, "");
Here are some quick solutions with .NET regex:
To remove any whitespace from a string: s = Regex.Replace(s, #"\s+", ""); (\s matches any Unicode whitespace chars)
To remove all whitespace BUT CR and LF: s = Regex.Replace(s, #"[\s-[\r\n]]+", ""); ([\s-[\r\n]] is a character class containing a subtraction construct, it matches any whitespace but CR and LF)
To remove any vertical whitespace, subtract \p{Zs} (any horizontal whitespace but tab) and \t (tab) from \s: s = Regex.Replace(s, #"[\s-[\p{Zs}\t]]+", "");.
Wrapping the last one into an extension method:
public static string RemoveLineEndings(this string value)
{
return Regex.Replace(value, #"[\s-[\p{Zs}\t]]+", "");
}
See the regex demo.
I have the following input:
string txt = " i am a string "
I want to remove space from start of starting and end from a string.
The result should be: "i am a string"
How can I do this in c#?
String.Trim
Removes all leading and trailing white-space characters from the current String object.
Usage:
txt = txt.Trim();
If this isn't working then it highly likely that the "spaces" aren't spaces but some other non printing or white space character, possibly tabs. In this case you need to use the String.Trim method which takes an array of characters:
char[] charsToTrim = { ' ', '\t' };
string result = txt.Trim(charsToTrim);
Source
You can add to this list as and when you come across more space like characters that are in your input data. Storing this list of characters in your database or configuration file would also mean that you don't have to rebuild your application each time you come across a new character to check for.
NOTE
As of .NET 4 .Trim() removes any character that Char.IsWhiteSpace returns true for so it should work for most cases you come across. Given this, it's probably not a good idea to replace this call with the one that takes a list of characters you have to maintain.
It would be better to call the default .Trim() and then call the method with your list of characters.
You can use:
String.TrimStart - Removes all leading occurrences of a set of characters specified in an array from the current String object.
String.TrimEnd - Removes all trailing occurrences of a set of characters specified in an array from the current String object.
String.Trim - combination of the two functions above
Usage:
string txt = " i am a string ";
char[] charsToTrim = { ' ' };
txt = txt.Trim(charsToTrim)); // txt = "i am a string"
EDIT:
txt = txt.Replace(" ", ""); // txt = "iamastring"
I really don't understand some of the hoops the other answers are jumping through.
var myString = " this is my String ";
var newstring = myString.Trim(); // results in "this is my String"
var noSpaceString = myString.Replace(" ", ""); // results in "thisismyString";
It's not rocket science.
txt = txt.Trim();
Or you can split your string to string array, splitting by space and then add every item of string array to empty string.
May be this is not the best and fastest method, but you can try, if other answer aren't what you whant.
text.Trim() is to be used
string txt = " i am a string ";
txt = txt.Trim();
Use the Trim method.
static void Main()
{
// A.
// Example strings with multiple whitespaces.
string s1 = "He saw a cute\tdog.";
string s2 = "There\n\twas another sentence.";
// B.
// Create the Regex.
Regex r = new Regex(#"\s+");
// C.
// Strip multiple spaces.
string s3 = r.Replace(s1, #" ");
Console.WriteLine(s3);
// D.
// Strip multiple spaces.
string s4 = r.Replace(s2, #" ");
Console.WriteLine(s4);
Console.ReadLine();
}
OUTPUT:
He saw a cute dog.
There was another sentence.
He saw a cute dog.
You Can Use
string txt = " i am a string ";
txt = txt.TrimStart().TrimEnd();
Output is "i am a string"
How can I remove all white space from the beginning and end of a string?
Like so:
"hello" returns "hello"
"hello " returns "hello"
" hello " returns "hello"
" hello world " returns "hello world"
String.Trim() returns a string which equals the input string with all white-spaces trimmed from start and end:
" A String ".Trim() -> "A String"
String.TrimStart() returns a string with white-spaces trimmed from the start:
" A String ".TrimStart() -> "A String "
String.TrimEnd() returns a string with white-spaces trimmed from the end:
" A String ".TrimEnd() -> " A String"
None of the methods modify the original string object.
(In some implementations at least, if there are no white-spaces to be trimmed, you get back the same string object you started with:
csharp> string a = "a";
csharp> string trimmed = a.Trim();
csharp> (object) a == (object) trimmed;
returns true
I don't know whether this is guaranteed by the language.)
take a look at Trim() which returns a new string with whitespace removed from the beginning and end of the string it is called on.
string a = " Hello ";
string trimmed = a.Trim();
trimmed is now "Hello"
use the String.Trim() function.
string foo = " hello ";
string bar = foo.Trim();
Console.WriteLine(bar); // writes "hello"
Use String.Trim method.
String.Trim() removes all whitespace from the beginning and end of a string.
To remove whitespace inside a string, or normalize whitespace, use a Regular Expression.
Trim()
Removes all leading and trailing white-space characters from the current string.
Trim(Char)
Removes all leading and trailing instances of a character from the current string.
Trim(Char[]) Removes all leading and trailing occurrences of a set of characters specified in an array from the current string.
Look at the following example that I quoted from Microsoft's documentation page.
char[] charsToTrim = { '*', ' ', '\''};
string banner = "*** Much Ado About Nothing ***";
string result = banner.Trim(charsToTrim);
Console.WriteLine("Trimmmed\n {0}\nto\n '{1}'", banner, result);
// The example displays the following output:
// Trimmmed
// *** Much Ado About Nothing ***
// to
// 'Much Ado About Nothing'
How can I replace Line Breaks within a string in C#?
Use replace with Environment.NewLine
myString = myString.Replace(System.Environment.NewLine, "replacement text"); //add a line terminating ;
As mentioned in other posts, if the string comes from another environment (OS) then you'd need to replace that particular environments implementation of new line control characters.
The solutions posted so far either only replace Environment.NewLine or they fail if the replacement string contains line breaks because they call string.Replace multiple times.
Here's a solution that uses a regular expression to make all three replacements in just one pass over the string. This means that the replacement string can safely contain line breaks.
string result = Regex.Replace(input, #"\r\n?|\n", replacementString);
To extend The.Anyi.9's answer, you should also be aware of the different types of line break in general use. Dependent on where your file originated, you may want to look at making sure you catch all the alternatives...
string replaceWith = "";
string removedBreaks = Line.Replace("\r\n", replaceWith).Replace("\n", replaceWith).Replace("\r", replaceWith);
should get you going...
I would use Environment.Newline when I wanted to insert a newline for a string, but not to remove all newlines from a string.
Depending on your platform you can have different types of newlines, but even inside the same platform often different types of newlines are used. In particular when dealing with file formats and protocols.
string ReplaceNewlines(string blockOfText, string replaceWith)
{
return blockOfText.Replace("\r\n", replaceWith).Replace("\n", replaceWith).Replace("\r", replaceWith);
}
If your code is supposed to run in different environments, I would consider using the Environment.NewLine constant, since it is specifically the newline used in the specific environment.
line = line.Replace(Environment.NewLine, "newLineReplacement");
However, if you get the text from a file originating on another system, this might not be the correct answer, and you should replace with whatever newline constant is used on the other system. It will typically be \n or \r\n.
if you want to "clean" the new lines, flamebaud comment using regex #"[\r\n]+" is the best choice.
using System;
using System.Text.RegularExpressions;
class MainClass {
public static void Main (string[] args) {
string str = "AAA\r\nBBB\r\n\r\n\r\nCCC\r\r\rDDD\n\n\nEEE";
Console.WriteLine (str.Replace(System.Environment.NewLine, "-"));
/* Result:
AAA
-BBB
-
-
-CCC
DDD---EEE
*/
Console.WriteLine (Regex.Replace(str, #"\r\n?|\n", "-"));
// Result:
// AAA-BBB---CCC---DDD---EEE
Console.WriteLine (Regex.Replace(str, #"[\r\n]+", "-"));
// Result:
// AAA-BBB-CCC-DDD-EEE
}
}
Use new in .NET 6 method
myString = myString.ReplaceLineEndings();
Replaces ALL newline sequences in the current string.
Documentation:
ReplaceLineEndings
Don't forget that replace doesn't do the replacement in the string, but returns a new string with the characters replaced. The following will remove line breaks (not replace them). I'd use #Brian R. Bondy's method if replacing them with something else, perhaps wrapped as an extension method. Remember to check for null values first before calling Replace or the extension methods provided.
string line = ...
line = line.Replace( "\r", "").Replace( "\n", "" );
As extension methods:
public static class StringExtensions
{
public static string RemoveLineBreaks( this string lines )
{
return lines.Replace( "\r", "").Replace( "\n", "" );
}
public static string ReplaceLineBreaks( this string lines, string replacement )
{
return lines.Replace( "\r\n", replacement )
.Replace( "\r", replacement )
.Replace( "\n", replacement );
}
}
To make sure all possible ways of line breaks (Windows, Mac and Unix) are replaced you should use:
string.Replace("\r\n", "\n").Replace('\r', '\n').Replace('\n', 'replacement');
and in this order, to not to make extra line breaks, when you find some combination of line ending chars.
Why not both?
string ReplacementString = "";
Regex.Replace(strin.Replace(System.Environment.NewLine, ReplacementString), #"(\r\n?|\n)", ReplacementString);
Note: Replace strin with the name of your input string.
I needed to replace the \r\n with an actual carriage return and line feed and replace \t with an actual tab. So I came up with the following:
public string Transform(string data)
{
string result = data;
char cr = (char)13;
char lf = (char)10;
char tab = (char)9;
result = result.Replace("\\r", cr.ToString());
result = result.Replace("\\n", lf.ToString());
result = result.Replace("\\t", tab.ToString());
return result;
}
var answer = Regex.Replace(value, "(\n|\r)+", replacementString);
As new line can be delimited by \n, \r and \r\n, first we’ll replace \r and \r\n with \n, and only then split data string.
The following lines should go to the parseCSV method:
function parseCSV(data) {
//alert(data);
//replace UNIX new lines
data = data.replace(/\r\n/g, "\n");
//replace MAC new lines
data = data.replace(/\r/g, "\n");
//split into rows
var rows = data.split("\n");
}
Use the .Replace() method
Line.Replace("\n", "whatever you want to replace with");
Best way to replace linebreaks safely is
yourString.Replace("\r\n","\n") //handling windows linebreaks
.Replace("\r","\n") //handling mac linebreaks
that should produce a string with only \n (eg linefeed) as linebreaks.
this code is usefull to fix mixed linebreaks too.
Another option is to create a StringReader over the string in question. On the reader, do .ReadLine() in a loop. Then you have the lines separated, no matter what (consistent or inconsistent) separators they had. With that, you can proceed as you wish; one possibility is to use a StringBuilder and call .AppendLine on it.
The advantage is, you let the framework decide what constitutes a "line break".
string s = Regex.Replace(source_string, "\n", "\r\n");
or
string s = Regex.Replace(source_string, "\r\n", "\n");
depending on which way you want to go.
Hopes it helps.
If you want to replace only the newlines:
var input = #"sdfhlu \r\n sdkuidfs\r\ndfgdgfd";
var match = #"[\\ ]+";
var replaceWith = " ";
Console.WriteLine("input: " + input);
var x = Regex.Replace(input.Replace(#"\n", replaceWith).Replace(#"\r", replaceWith), match, replaceWith);
Console.WriteLine("output: " + x);
If you want to replace newlines, tabs and white spaces:
var input = #"sdfhlusdkuidfs\r\ndfgdgfd";
var match = #"[\\s]+";
var replaceWith = "";
Console.WriteLine("input: " + input);
var x = Regex.Replace(input, match, replaceWith);
Console.WriteLine("output: " + x);
This is a very long winded one-liner solution but it is the only one that I had found to work if you cannot use the the special character escapes like "\r" and "\n" and \x0d and \u000D as well as System.Environment.NewLine as parameters to thereplace() method
MyStr.replace( System.String.Concat( System.Char.ConvertFromUtf32(13).ToString(), System.Char.ConvertFromUtf32(10).ToString() ), ReplacementString );
This is somewhat offtopic but to get it to work inside Visual Studio's XML .props files, which invoke .NET via the XML properties, I had to dress it up like it is shown below.
The Visual Studio XML --> .NET environment just would not accept the special character escapes like "\r" and "\n" and \x0d and \u000D as well as System.Environment.NewLine as parameters to thereplace() method.
$([System.IO.File]::ReadAllText('MyFile.txt').replace( $([System.String]::Concat($([System.Char]::ConvertFromUtf32(13).ToString()),$([System.Char]::ConvertFromUtf32(10).ToString()))),$([System.String]::Concat('^',$([System.Char]::ConvertFromUtf32(13).ToString()),$([System.Char]::ConvertFromUtf32(10).ToString())))))
Based on #mark-bayers answer and for cleaner output:
string result = Regex.Replace(ex.Message, #"(\r\n?|\r?\n)+", "replacement text");
It removes \r\n , \n and \r while perefer longer one and simplify multiple occurances to one.