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Is there a possibility to write or print \ into a console

I have a question. Can I write \ into a conosle in vscode? I tried to print an ascii character into the console for my little project that I am working on, because I am trying to learn c#
I have tired everything and the only thing I get is this message: the constant contains the newline character.
I know what it means because \n make a new line. I tried to search the internet and I didnt see anything related to what I am asking. Any help?
Thank you for seeing this question
-Henry

The backslash (\) is used as an escape character in C#. You can find the documentation about escape sequences here
When you type just one backslash, the compiler will therefore interpret this character (and the next one) as an escape sequence.
Like Progman suggested, you can type "\\" to display a backslash in the Console.

Yes, you can print \ on console.
\ is actually an escape sequence, hence the confusion.
Check this for escape sequences : here
To print "\" on the console in C# -
Console.WriteLine("Print \\");

C# regex.escape unexpected behavior when processing "."

Hey I have an issue with Regex.Escape I'm trying to feed it an Email from TextBox Controll. The function recieves "test#test.test". What I expect to get is this "test#test\.test" Regex.Escape escapes the dot character. Hovever what I get instead is "test#test\\.test" which is very confusing. I plan on handing that string down to an SQL query and I'm worried abut users misbehaving.
holder.address = Regex.Escape(EmailAddressInput.Text);
This is how I assign resulting string to field in holder class.
I have been researching this problem on my own but most sources (including MSDN) suggest to prefix the dot ("the special character") with one backslash.
As it is right now backslash escapes backslash and result is a badly formatted email address.

var s = "test#test\\.test"; means the s holds the test#test\.test string. Your issue does not exist. There is a single backslash. Click the magnifier button on the right - you will see that in the Text Visualizer.

Regex has to have \\ because its escaping the \
the string itself actually only has one \ in it.

Properly escape filepaths

How do I escape with the #-sign when using variables?
File.Delete(#"c:\test"); // WORKS!
File.Delete(#path); // doesn't work :(
File.Delete(#"c:\test"+path); // WORKS
Anyone have any idea? It's the 2nd example I want to use!

Strings prefixed with # character are called verbatim string literals (whose contents do not need to be escaped).
Therefore, you can only use # with string literals, not string variables.
So, just File.Delete(path); will do, after you assign the path in advance of course (from a verbatim string or some other string).

Verbatim strings are just a syntactic nicety to be able to type strings containing backslashes (paths, regexes) easier. The declarations
string path = "C:\\test";
string path = #"C:\test";
are completely identical in their result. Both result in a string containing C:\test. Note that either option is just needed because the C# language treats \ in strings as special.
The # is not some magic pixie dust needed to make paths work properly, it has a defined meaning when prefixed to strings, in that the strings are interpreted without the usual \ escape sequences.
The reason your second example doesn't work like you expect is that # prefixed to a variable name does something different: It allows you to use reserved keywords as identifiers, so that you could use #class as an identifier, for example. For identifiers that don't clash with keywords the result is the same as without.
If you have a string variable containing a path, then you can usually assume that there is no escaping needed at all. After all it already is in a string. The things I mentioned above are needed to get text from source code correctly through the compiler into a string at runtime, because the compiler has different ideas. The string itself is just data that's always represented the same.
This still means that you have to initialise the string in a way that backslashes survive. If you read it from somewhere no special treatment should be necessary, if you have it as a constant string somewhere else in the code, then again, one of the options at the top has to be used.

string path = #"c:\test";
File.Delete(path);
This will work only on a string. The "real" string is "c:\\test".
Read more here.

There's a major problem with your understanding of the # indicator.
#"whatever string" is a literal string specifier verbatim string literal. What it does is tells the C# compiler to not look for escape sequences. Normally, "\" is an escape sequence in a string, and you can do things like "\n" to indicate a new line or "\t" to indicate a tab. However, if you have #"\n", it tells the compiler "no, I really want to treat the backslash as a backslash character, not an escape sequence."
If you don't like literal mode, the way to do it is to use "\\" anywhere you want a single backslash, because the compiler knows to treat an escaped backslash as the single character.
In either case, #"\n" and "\\n" will produce a 2-character string in memory, with the characters '\' and 'n'. It doesn't matter which way you get there; both are ways of telling the compiler you want those two characters.
In light of this, #path makes no sense, because you don't have any literal characters - just a variable. By the time you have the variable, you already have the characters you want in memory. It does compile ok, as explained by Joey, but it's not logically what you're looking for.
If you're looking for a way to get rid of occurrences of \\ within a variable, you simply want String.Replace:
string ugly = #"C:\\foo";
ugly = ugly.Replace(#"\\", #"\");

First and third are actual paths hence would work.
Second would not even compile and would work if
string path = #"c:\test";
File.Delete(path);

Escape single and double back slashes

I am trying to replace a string using regex, however I can't seem to find a way to escape the single backslashes for the regex with the double backslashes of the string.
My string literal (this is being read from a text file, as is)
-s \"t\"
and I want to replace it with (again, as a string literal)
-s \"n\"
The best I have been able to come up with is
schedule = Regex.Replace(schedule, "-s\s\\\"\w\\\"", "-s \\\"n\\\"");
The middle argument doesn't compile though, because of the single and double backslashes. It will accept one or the other, but not both (regardless of weather I use #).
I don't use regexes that much so it may be a simple one but I'm pretty stuck!
Thanks

The problem is happening because \ have a special meaning both for strings and regular expressions so it normally needs to be double escaped unless you use # and added to the problem here is the presence of " itself inside the string which needs to be escaped.
Try the following:
schedule = Regex.Replace(schedule, #"-s\s\\""\w\\""", #"-s \""n\""");
After using #, \ doesn't have a special meaning inside strings, but it still have a special meaning inside regular expression expression so it needs to be escaped only once if it is needed literally.
Also now you need to use "" to escape " inside the string (how would you escape it otherwise, since \ doesn't have a special meaning anymore).

This works:
var schedule = #"-s \""t\""";
// value is -s \"t\"
schedule = Regex.Replace(schedule, #"-s\s\\""\w\\""", #"-s \""n\""");
// value is -s \"n\"
The escaping is complicated because \ and " have special meanings both in how you encode strings in C# and in regex. The search pattern is (without any escaping) the C# string -s\s\\"\w\\", which tells regex to look for a literal \ and a literal ". The replacement string is -s \"n\", because you don't need to escape the backslashes in a replacement string.
You could, of course, write this with normal strings ("...") instead of verbatim strings (#"..."), but it'd get way messier.

Replacing a specific character with string.replace()

I'd like to replace all occurences of / to \ . i used this snippet:
_url = _url.Replace("/",#"\");
but it replaces / to \\.
Why this happens? How can i modify the snippet to get a good result

Your string most likely already contains a single backslash!
I suspect your string already actually only contains a single backslash,
but you're looking at it in the debugger which is escaping it for you into
a form which would be valid as a regular string literal in C#.
quoted Jon Skeet from: Replace "\\" with "\" in a string in C#

I'm going to guess that you attempted to verify correct operation in the debugger. Visual Studio's debugger tips escape backslash characters, so if you see \\ in the tooltip then the string actually contains only 1 backslash. Click the magnifying glass icon at the end of the tooltip in the debugger to bring up a dialog containing the unescaped text.
Edit: This applies to the watch windows as well, including the part about the magnifying glass at the end.