I'm trying to set the value of a string to something that has a \ in it, but cannot do so as they say I have an unrecognized escape sequence. Is it possible to write \ in a string?
You must escape it... if you are using a regular string you must double the slash "hello\\world" or if you want it as a literal you can use #"hello\world"
Yes, just change the \ to a \\.
You can read more about Escape Sequences here.
All the above answers are right. I want to include one more way of doing the same i.e. by using a unicode character.
e.g. the \u005c represents "\"
hence "hello \u005c world"; will give the output as hello \ world
All the below will give the same result
string test1 = "hello \\ world";
string test2 = #"hello \ world";
string test3 = "hello \u005c world";
For a list of unicode character set visit this site
Thanks
like others have pointed out, use double slash "\\"
OR you can change your string to a string literal, and not have to update your slashes...
eg
string a = #"some s\tring wi\th slashes";
Alternatively, you can prefix the string with #, which will tell the compiler to interpret the string literally.
string str = #"i am using \ in a string";
Yes, use "\\".
For an explanation and a list of possible escape symbols, see http://msdn.microsoft.com/en-us/library/ms228362.aspx .
Related
string s = "P\04";
string z = s.Replace('\\', '-');
Console.WriteLine(z);
I need to replace '\' character in to '-' character in a string. I tried several ways to replace, couldn't able to do for '\' character only.
Please any one suggest a way to do this
Your code to replace the \ is fine. The problem is with your input string, where the \ escapes the 0. It would work if you had this:
string s = "P\\04";
string z = s.Replace('\\', '-');
Console.WriteLine(z);
The output is P-04 assuming that's what you expect.
string s = #"P\04";
string z = s.Replace('\\', '-');
Console.WriteLine(z);
Add # at the before value of string s to make it a verbatim. That way '\' is treated as is. Otherwise \0 are treated as one character to make a different character.
You can also use Regex,
var result = Regex.Replace(#"P\04", #"\\", #"-");
Console.WriteLine(result);
FIDDLE
I have a string that contains sequence of three "\" and I have to replace them with single "\".
the string is:
string sample = "<ArrayOfMyObject xmlns:i=\\\"http://www.w3.org/2001/XMLSchema-instance\\\"";
I have tried, as suggested in other threads, with the following code but it did not work:
string result = sample.Replace(#"\\\",#"\");
string result = sample.Replace("\\\\\\","\\");
thanks in advance
In your sample, your string doesn't actually have three "\" characters in it - Some of them are escape characters.
\ will actually correspond to a single \ character.
\" will actually correspond to a single " character.
The value of your string, in memory, is:-
<ArrayOfMyObject xmlns:i=\"http://www.w3.org/2001/XMLSchema-instance\"
So, your replace operations do nothing because they do not match anything.
To replace \\\ with \ in a c# string try this code (tested and working)
string strRegex = #"(\\){3}";
string strTargetString = #"sett\\\abc";
var test=Regex.Replace(strTargetString, strRegex, #"\"); //test becomes sett\abc
in debug you will see test=sett\\abc (2 backslashes but one is an escape).
Don't worry and go to text Visualizer and you'll see the correct value
then
in your specific case the code will be
string sample = #"<ArrayOfMyObject xmlns:i=\\\"http://www.w3.org/2001/XMLSchema-instance\\\"";
var result=Regex.Replace(sample , strRegex, #"\");
the output of both of the replaces is
<ArrayOfMyObject xmlns:i=\"http://www.w3.org/2001/XMLSchema-instance\"
this looks correct
but maybe you have to add 6 instead of 3 '\' in your input, because there caracters are escape characters.
Input String is "How are you"
Expected output \"How are you\"
Due to combination of DoubleQuote and escape sequence I am not able to replace the string in the required format.
Please can someone provide me the code snippet for doing this.
I have tried below does not work
myString.Replace(""","\"");
Yes, that looks a little bit weird, you need to escape both:
string test = "\"How are you\"";
test = test.Replace("\"", "\\\"");
Both " and \ have special meaning within a string literal and must be escaped with \.
So something like this:
myString.Replace("\"","\\\"");
Escape your backslash
myString.Replace("\"","\\\"");
This:
"\\\""
produces this:
\"
And also you should escape your double quote in first parameter.
And you can use verbatim strings,but there is a weird case about double quote, instead of \" you should use two double quotes "" to escepe your charachter:
myString.Replace(#"""",#"\""");
string myString = "\"How are you\"";
myString = myString.Replace("\"", "\\\"");
This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
What does # mean at the start of a string in C#?
Sorry but I can't find this on Google. I guess it maybe is not accepting my search string when I do a search.
Can someone tell me what this means in C#
var a = #"abc";
what's the meaning of the #?
It is a string literal. Which basically means it will take any character except ", including new lines. To write out a ", use "".
The advantage of #-quoting is that escape sequences are not processed,
which makes it easy to write, for example, a fully qualified file
name:
#"c:\Docs\Source\a.txt" // rather than "c:\\Docs\\Source\\a.txt"
It means it's a literal string.
Without it, any string containing a \ will consider the next character a special character, such as \n for new line. With a # in front, it will treat the \ literally.
In the example you've given, there is no difference in the output.
This says that the characters inside the double quotation marks should be interpreted exactly as they are.
You can see that the backslash is treated as a character and not an
escape sequence when the # is used. The C# compiler also allows you to
use real newlines in verbatim literals. You must encode quotation
marks with double quotes.
string fileLocation = "C:\\CSharpProjects";
string fileLocation = #"C:\CSharpProjects";
Look at here for examples.
C# supports two forms of string literals: regular string literals and verbatim string literals.
A regular string literal consists of zero or more characters enclosed
in double quotes, as in "hello", and may include both simple escape
sequences (such as \t for the tab character) and hexadecimal and
Unicode escape sequences.
A verbatim string literal consists of an # character followed by a
double-quote character, zero or more characters, and a closing
double-quote character. A simple example is "hello". In a verbatim
string literal, the characters between the delimiters are interpreted
verbatim, the only exception being a quote-escape-sequence. In
particular, simple escape sequences and hexadecimal and Unicode
escape sequences are not processed in verbatim string literals. A
verbatim string literal may span multiple lines.
Code Example
string a = "hello, world"; // hello, world
string b = #"hello, world"; // hello, world
string c = "hello \t world"; // hello world
string d = #"hello \t world"; // hello \t world
string e = "Joe said \"Hello\" to me"; // Joe said "Hello" to me
string f = #"Joe said ""Hello"" to me"; // Joe said "Hello" to me
string g = "\\\\server\\share\\file.txt"; // \\server\share\file.txt
string h = #"\\server\share\file.txt"; // \\server\share\file.txt
string i = "one\r\ntwo\r\nthree";
string j = #"one
two
three";
Reference link: MSDN
The following code generates a compiler error about an "unrecognized escape sequence" for each backslash:
string foo = "D:\Projects\Some\Kind\Of\Pathproblem\wuhoo.xml";
I guess I need to escape backslash? How do I do that?
You can either use a double backslash each time
string foo = "D:\\Projects\\Some\\Kind\\Of\\Pathproblem\\wuhoo.xml";
or use the # symbol
string foo = #"D:\Projects\Some\Kind\Of\Pathproblem\wuhoo.xml";
Try this:
string foo = #"D:\Projects\Some\Kind\Of\Pathproblem\wuhoo.xml";
The problem is that in a string, a \ is an escape character. By using the # sign you tell the compiler to ignore the escape characters.
You can also get by with escaping the \:
string foo = "D:\\Projects\\Some\\Kind\\Of\\Pathproblem\\wuhoo.xml";
var foo = #"D:\Projects\Some\Kind\Of\Pathproblem\wuhoo.xml";
If your string is a file path, as in your example, you can also use Unix style file paths:
string foo = "D:/Projects/Some/Kind/Of/Pathproblem/wuhoo.xml";
But the other answers have the more general solutions to string escaping in C#.
string foo = "D:\\Projects\\Some\\Kind\\Of\\Pathproblem\\wuhoo.xml";
This will work, or the previous examples will, too. #"..." means treat everything between the quote marks literally, so you can do
#"Hello
world"
To include a literal newline. I'm more old school and prefer to escape "\" with "\\"