Is there another way of assigning string path to variable aside from this:
strPath = #"C:\Myfile.txt";
is there another way instead using "#" sign in the string path.
thanks.
You can escape it:
var myPath = "C:\\MyFile.txt"
Do you mean another way of escaping the backslashes?
The # sign at the start means that the string is treated as a verbatim string literal, and simple escape sequences such as \n or \t are ignored.
If you don't put the # at the start it is not verbatim, and escape sequences are parsed. If you want to ignore an individual escape sequence you can precede it with a single backslash and it will be ignored.
The reason you would use it in a path such as your example is so that you don't have to escape each individual backslash as you would if you didn't put the # at the start:
strPath = "C:\\Myfile.txt";
You can use forward slashes and it'll work fine on Windows and no escaping needed.
strPath = "C:/Myfile.txt";
You can use Unicode Escape Sequences....
string strPath = "C:\u005CMyfile.txt";
string path = Path.Combine("C:", "myfile.txt");
Related
Using C# in Visual Studio 13 - I'm trying to replace some slashes in my string using the replace command. The VS tool tip tells me, "Returns a new string in which all occurrences of a specified Unicode character in this instance are replaced with another specified Unicode character"
My string, which is passed in as a parameter is:
path = "\\\\ServerName\\Folder1\\Folder2"
I create a new string:
string newPath = path.Replace(#"\\", #"//");
According to the tool tip it should replace all instances of \\ with //, but instead my resulting string is:
"//\\ServerName\\Folder1\\Folder2"
What am I doing wrong? It seemed pretty straight forward to me, or so I thought.
What I'm trying to get is:
"////ServerName//Folder1//Folder2"
Your output will be //ServerName\Folder2\Folder2, as there is only one actual occurrence of two backslashes, namely at the beginning of \\ServerName.
When inspecting a string's value, the debugger shows a single backslash (\) as two (\\), but when replacing, you want to replace one:
string newPath = path.Replace(#"\", #"/");
Note that you don't need to escape a slash character (/).
Try this:
string newPath = path.Replace("\\", "/");
Your path string really is: #"\\ServerName\Folder1\Folder2".
Perhaps I didn't see or understand any of the answers I read but I am having trouble using verbatim string literal (#) with settings.Default.(mysetting). I am trying to do something like
Directory.GetFiles(#Setting.Default.(mysetting),"*.txt");
and cant seem to find the right syntax to make this work.
The # identifies a string constant literal where back slashes should not be interpreted as escape signs. You can not use it in front of method invocations as you attempt here.
A valid assignment might be
string path = #"c:\temp\example.txt";
Usually a \t would be interpreted as a tabulation character thus making the file reference illegal. It is exactly identical to
string path = "c:\\temp\\example.txt" ;
But bit easier to read.
# verbatim string is used with string literals. So your code should be:
Directory.GetFiles(Setting.Default.(mysetting),#"*.txt");
because "*.txt" is the string literal in your code.
(Although not related, but you can use # with variable names see C# Variable Naming and the # Symbol)
To use # as part of a verbatim string literal, the string literal must be right there - not just a property, method, etc. that returns a string.
string myStr = #"I'm verbatim, I contain a literal \n";
string myStr2 = "I'm not\nI have a newline";
string myStr3 = #myStr2; // still contains a newline, not a literal "\n"
Using # in front of an identifier allows you to use reserved keywords as identifiers. For example:
string #if = "hello!"; // valid
It also works on non-reserved words, where it has no real effect.
string #myVar = "hello!"; // valid
string newVar = myVar; // can be referred to either way
Unless I'm missing it, you still need to wrap the string within quotation marks.
I want to write something like this C:\Users\UserName\Documents\Tasks in a textbox:
txtPath.Text = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments)+"\Tasks";
I get the error:
Unrecognized escape sequence.
How do I write a backslash in a string?
The backslash ("\") character is a special escape character used to indicate other special characters such as new lines (\n), tabs (\t), or quotation marks (\").
If you want to include a backslash character itself, you need two backslashes or use the # verbatim string:
var s = "\\Tasks";
// or
var s = #"\Tasks";
Read the MSDN documentation/C# Specification which discusses the characters that are escaped using the backslash character and the use of the verbatim string literal.
Generally speaking, most C# .NET developers tend to favour using the # verbatim strings when building file/folder paths since it saves them from having to write double backslashes all the time and they can directly copy/paste the path, so I would suggest that you get in the habit of doing the same.
That all said, in this case, I would actually recommend you use the Path.Combine utility method as in #lordkain's answer as then you don't need to worry about whether backslashes are already included in the paths and accidentally doubling-up the slashes or omitting them altogether when combining parts of paths.
To escape the backslash, simply use 2 of them, like this:
\\
If you need to escape other things, this may be helpful..
There is a special function made for this Path.Combine()
var folder = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
var fullpath = path.Combine(folder,"Tasks");
Just escape the "\" by using + "\\Tasks" or use a verbatim string like #"\Tasks"
txtPath.Text = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments)+"\\\Tasks";
Put a double backslash instead of a single backslash...
even though this post is quite old I tried something that worked for my case .
I wanted to create a string variable with the value below:
21541_12_1_13\":null
so my approach was like that:
build the string using verbatim
string substring = #"21541_12_1_13\"":null";
and then remove the unwanted backslashes using Remove function
string newsubstring = substring.Remove(13, 1);
Hope that helps.
Cheers
I have a short question.
I want do put this \tssr>"&\8=f23' into a String (Language C#).
But the compiler always shows an error because for example "\8" is a command.
can someone help me?
Thank you very mutch.
string s = "\\tssr>\"&\\8=f23'";
OR
string s = #"\tssr>""&\8=f23'";
try
string s = #"\tssr>\"&\8=f23";
For double quote[EDIT]
string s = #"\tssr>""&\8=f23";
because \ is special char you need to escape it with either # for \\ as given in below answer
Just write \\8 instead of \8. Or put an # in front of the string. Other characters also need to be escaped with the \ character:
"\\tssr>\"&\\8=f23'"
or this:
#"\tssr>""&\8=f23'"
the backslash \ is used for escaping special characters, like tab or newline. Because of that, the first character also needs to be escaped, because \t is the escape code for Tab.
Try escape sequence
Check this
\\tssr>\"&\\8=f23\'
See below.
var str = "\\tssr>\"&\\8=f23'";
I add a backslash to escape the special characters
The backslash is an escape character in C#, which forms part of an escape sequence.
You have two options: either use TWO backslashes (also known as escaping the backslash) for example var foo = "hello\\world";, or embed the sequence into a string literal eg var foo = #"hello\world";.
Try this:
string s = " \\tssr>\"&\\8=f23' ";
This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
What's the # in front of a string for .NET?
I understand using the # symbol is like an escape character for a string.
However, I have the following line as a path to store a file to a mapped network drive:
String location = #"\\192.168.2.10\datastore\\" + id + "\\";
The above works fine but now I would like to get a string from the command line so I have done this:
String location = #args[0] + id + "\\";
The above doesn't work and it seems my slashes aren't ignored. This my command:
MyProgram.exe "\\192.168.2.10\datastore\\"
How can I get the effect of the # symbol back?
It is used for two things:
create "verbatim" strings (ignores the escape character): string path = #"C:\Windows"
escape language keywords to use them as identifiers: string #class = "foo"
In your case you need to do this:
String location = args[0] + id + #"\\";
The # symbol in front of a string literal tells the compiler to ignore and escape sequences in the string (ie things that begin with a slash) and just to create the string "as-is"
It can also be used to create variables whose name is a reserved work. For example:
int #class=10;
If you don't prefix the # then you'd get a compile-time error.
You can also prefix it to variables that are not reserved word:
int #foo=22;
Note that you can refer to the variable as foo or #foo in your code.
The # prefix means the string is a literal string and the processing of escape characters is not performed by the compiler, so:
#"\n"
is not translated to a newline character. Without it, you'd have:
String location = "\\\\192.168.2.10\\datastore\\\\" + id + "\\\\";
which looks a bit messy. The '#' tidies things up a bit. The '#' can only be prefixed to string constants, that is, things inside a pair of double quotes ("). Since it is a compiler directive it is only applied at compile time so the string must be known at compile time, hence,
#some_string_var
doesn't work the way you think. However, since all the '#' does is stop processing of escaped characters by the compiler, a string in a variable already has the escaped character values in it (10,13 for '\n', etc). If you want to convert a '\n' to 10,13 for example at run time you'll need to parse it yourself doing the required substitutions (but I'm sure someone knows a better way).
To get what you want, do:
String location = args[0] + id + "\\";
The # symbol has two uses in C#.
To use a quotes instead of escaping. "\windows" can be represented as #"\windows". "\"John!\"" can be represented #"""John!""".
To escape variable names (for example to use a keyword as a parameter name)
private static void InsertSafe (string item, object #lock)
{
lock (#lock)
{
mylist.Insert(0,item);
}
}
#-quoted string literals start with # and are enclosed in double quotation marks. For example:
#"good morning" // a string literal
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"
To include a double quotation mark in an #-quoted string, double it:
#"""Ahoy!"" cried the captain." // "Ahoy!" cried the captain.
Another use of the # symbol is to use referenced (/reference) identifiers that happen to be C# keywords. For more information, see 2.4.2 Identifiers.
http://msdn.microsoft.com/en-us/library/362314fe(v=vs.71).aspx
In this case you may not need to use #; just make it
String location = args[0] + id + "\\";
The # symbol is only relevant for string literals in code. Variables should never modify the contents of a string.
The # symbol goes right before the quotes. It only works on string literals, and it simply changes the way the string is understood by the compiler. The main thing it does is cause \ to be interpreted as a literal backslash, rather than escaping the next character. So you want:
String location = args[0] + id + #"\\";
By default the '\' character is an escape character for strings in C#. That means that if you want to have a backslash in your string you need two slashes the first to escape the second as follows:
string escaped = "This is a backslash \\";
//The value of escaped is - This is a backslash \
An easier example to follow is with the use of quotes:
string escaped = "To put a \" in a string you need to escape it";
//The value of escaped is - To put a " in a string you need to escape it
The # symbol is the equivalent of "ignore all escape characters in this string" and declare it verbatim. Without it your first declaration would look like this:
"\\\\192.168.2.10\\datastore\\\\" + id + "\\";
Note that you already didn't have the # on your second string, so that string hasn't changed and still only contains a single backslash.
You only need to use the # symbol when you are declaring strings. Since your argument is already declared it is not needed. So your new line can be:
String location = args[0] + id + "\\";
or
String location = args[0] + id + #"\";
If you load from the command line, it will already be escaped for you. This is why your escapes are "ignored" from your perspective. Note that the same is true when you load from config, so don't do this:
<add key="pathToFile" value="C:\\myDirectory\\myFile.txt"/>
If you do, you end up with double strings, as ".NET" is smart enough to escape thins for you when you load them in this manner.