Given the string "a|bc\de,fg~h,ijk,lm|no\p" what is the best way to add a '\' before the '|' ',' '~' and '\'
So the end string would be "a\|bc\de\,fg\~h\,ijk\,lm\|no\p"
What is the best way to do this?
I need this in c#.
Then i also need a way to get this string in JavaScript and remove all extra backslashes.
Thank you in advance.
EDIT
Can any one help me the the javacsript function that will give me back the original string, take off the extra \?
Regex would be overkill. Use String.Replace Method (String, String):
string myString = #"a|bc\de,fg~h,ijk,lm|no\p";
myString = myString.Replace("|", "\\|").Replace(",", "\\,").Replace("~", "\\~").Replace("\\", "\\\\");
This produces "a\|bc\\de\,fg\~h\,ijk\,lm\|no\\p"
There's probably more than one way to get the string out for JavaScript. It will depend on where you're generating the string. For illustration purposes, say you're generating the string in the code behind and putting it in some control (like a hidden field, perhaps) on the client.
In the client you would get the string and use the Javascript String.Replace method, something like this, assuming str1 is "a\|bc\\de\,fg\~h\,ijk\,lm\|no\\p":
str1 = str1.Replace("\,", ",");
str1 = str1.Replace("\|", ",");
str1 = str1.Replace("\\", "\");
It's been a while since I've done JavaScript, so you may need to escape the backslash with another backslash (like \\).
If you need to escape only Regex system characters, you can use the method Escape like that:
String str1= Regex.Escape("your string with \ - +");
No need to escape all and every character individually, put # before the string, for example:
string String = #"a|bc\de,fg~h,ijk,lm|no\p";
Related
I would like to know what is a good way to escape back slashes in a string without adding unnecessary slashes to it.
I mean, usually if I want to escape a backslash in a string, the simplest way is to use String.Replace() like so:
string s = someString.Replace("\\", "\\\\");
A similar thing can be done with regular expressions using Regex.Replace().
Now my question is, lets say I have a string that has some of its back slashes escaped like for example: "C:\some_folder\\some_file.bin"
Now if I try and replace the backslashes in that by adding another backslash before each occurrence, I will end up with the following string:
"C:\\some_folder\\\\some_file.bin"
No clearly, the \\\\ are unnecessary, so how do I go about ignoring already escaped characters?
I think, this is what you want to do-
string path = #"C:\some_folder\\some_file.bin";
string exactPath = string.Join("\\",path.Split(new char[] { '\\' }, StringSplitOptions.RemoveEmptyEntries));
here is a RegEx Approach
string Result = Regex.Replace("C:\\some_folder\\\\some_file.bin", "[\\\\]+", "\\");
in that case you need to escape for RegEx AND for C#. alternatively you can write
string Result = Regex.Replace(#"C:\some_folder\\some_file.bin",#"[\\]+",#"\");
because "\\" equals #"\"
Maybe I am missing something here
I have a variable dir coming in looking something like \\\\SERVERNAME\\dir\\subdir
I need it to look like \\SERVERNAME\dir\subdir
I used string.Replace routine but it did not replace the double slashes, the problem is that when i try to use the path as is, it doesn't find the file.
How would I use string.Replace here in order to get a valid path?
dir.Replace(#"\\", #"\") should do the trick.
In C# the backslash character, "\", is used to escape characters in strings. For example, in the string "Hello\nworld", the "\n" represents a newline character. So, in general, when C# sees a "\" in a string it expects to treat it as part of a special command character, rather than as a literal "\".
So, how do you tell C# that you want a literal backslash to appear in your string, that it isn't part of a special command character? You escape the backslash. And the escape character is also a backslash. So to tell C# that you really want a literal "\" to appear in your string (eg in a file path) you use two backslashes: "\\".
Say I wanted to set a variable to the following path: C:\Temp\FileDrop
In C# I'd have to do the following:
string myPath = "C:\\Temp\\FileDrop";
I suspect that when you see the value of a variable looking like \\\\SERVERNAME\\dir\\subdir it is escaping the backslash characters so the real value of the variable is \\SERVERNAME\dir\subdir.
By the way, if you're copying and pasting long paths from, say, Windows Explorer, it can be a real pain to have to double up the backslashes to escape them. So C# has a special string literal character, "#". If you prefix a string with a "#" then it will treat the string exactly as written. eg
string myPath = #"C:\Temp\FileDrop";
Please forgive me a beginner's question :)
string S="abc";
S+="\";
won't complile.
string S="abc";
S+="\\";
will make S="abc\\"
How can I make S="abc\" ?
Your second piece of code is what you want (or a verbatim string literal #"\" as others have suggested), and it only adds a single backslash - print it to the console and you'll see that.
These two pieces of code:
S += "\\";
and
S += #"\";
are exactly equivalent. In both cases, a single backslash is appended1.
I suspect you're getting confused by the debugger view, which escapes backslashes (and some other characters). You can validate that even with the debugger by looking at S.Length, which you'll see is 4 rather than 5.
1 Note that it doesn't change the data in the existing string, but it sets the value of S to refer to a new string which consists of the original with a backslash on the end. String objects in .NET are immutable - but that's a whole other topic...
Try this:
String S = "abc";
S += #"\";
# = verbatim string literal
http://msdn.microsoft.com/en-us/library/aa691090%28v=vs.71%29.aspx
http://msdn.microsoft.com/en-us/library/vstudio/362314fe.aspx
string S = "abs" + "\\";
Should and does result in abc\.
What you are probably seeing is the way the debugger/intellisense visualizes the string for you.
Try printing your string to the console or display it in a textbox.
You already have the solution. The reason it appears as abc\\ whilst debugging is because VS will escape backslashes, print the value of S to a console window and you'll see abc\.
You could add an # to the start of the string literal, e.g.
string S="abc";
S+= #"\";
Which will achieve the same thing.
You can escape the backslash with the # character:
string S="abc";
S += #"\";
But this accomplishes exactly what you've written in your second example. The confusion on this is stemming from the fact that the Visual Studio debugger continues to escape these characters, even though your source string will contain only a single backslash.
Your second example is perfectly fine
string S="abc";
S+="\\";
Visual studio displays string escaped, that's why you see two slashes in result string. If you don't want to use escaping declare string like this
#"\"
This is not compiling because compiler is expecting a character after escape symbol
string S="abc";
S+="\";
string S="abc";
S+="\\";
Console.WriteLine(S); // This is what you're missing ;)
You'll see your string is not wrong at all.
The backslash (\) is an escape character, and allows you to get special characters that you wouldn't normally be able to insert in a string, such as "\r\n", which represents a NewLine character, or "\"" which basically gives you a " character.
In order to get the \ character, you need to input "\\" which is exactly what you're doing and also what you want.
Using the verbatim (#) replaces all occurrences of \ into \\, so #"\" == "\\". This is usually used for paths and regexes, where literal \ are needed in great numbers. Saying #"C:\MyDirectory\MyFile" is more comfortable than "C:\\MyDirectory\\MyFile" after all.
Try this
string s="abc";
s = s+"\\";
We have the following code:
string str="\\u5b89\u5fbd\\";
We need output in the format:
"\u5b89\u5fbd\"
We have tried this code:
str.Replace("\\",#"\")
Its not working.
Try this
string str = "\\u5b89\u5fbd\\";
str = str.Replace(#"\\", #"\");
\ is a reserved sign. \\ escapes it and results in \
Adding # at the start of a string tell the compiler to use the string as is and not to escape characters.
So use either "\\\\" or #"\\"
EDIT
\\u5b89\u5fbd\\ actually does not have two \ together. \ is just escaped.
The string results in \u5b89徽\. And in that string you can't replace \\ because there is only one \ together.
Have you tried this?
str.Replace("\\\\","\\");
Your example accomplish nothing. "\\" is an escaped version of \, and #"\" is another version of writing \. So your example replaces \ with \
EDIT
Now I understand your problem. What you want can't actually be done, since that would cause the string to end with a single \, and that will not be allowed. \ denotes a start of a escape sequence, and needs something after it.
I think there are no good option here, since in your case \u5b89 is not a string, but an escape sequence for one specific character.
str.Replace("\\u5b89","\u5b89");
This works for your current example, but will only work with this one specific character, so I guess it wont help you much. The \ at the end you cannot replace with \, but I can't see why you need the string to end with this char either.
Your best bet is to make sure that the \ does not occur at the start of the string in the first place, instead of trying to get rid of it afterwards.
Okay so the first string is actually saved as:
"\u5b89[someChineseCharacter]\"
because you are already using escape sequences. If you would like the original string to be what you typed, you have to do it like so:
string str = #"\\u5b89\u5fbd\\";
Then, str = str.Replace(#"\\",#"\") would work.
Some clarification:
When you type string str="\\u5b89\u5fbd\\"; in visual studio, it saves the string \u5b89徽\ in memory, because you are using several escape sequences in the original statement:
\\ actually means \
\u5fbd actually means unicode character 5fbd, which is 徽.
For that reason, these get replaced, and in memory your string looks as mentioned.
So if you try to replace occurrences of two backslashes #"\\", it will appear to do nothing, because there were no such occurrences in the original string to begin with.
Hope this makes it clear.
Try this it will solve your problem.
str.Replace("\\\\","\\");
Or maybe Something like this?
foreach (char c in str)
{
if ((int)c < 256)
Console.Write(c);
else
Console.Write(String.Format("\\u{0:x4}", (int)c));
}
;)
Maybe it is just me but I think the input string should have a "\" in the middle, or the second u5fbd will be interpreted as a unicode char (so you won't get it outputted as you wish). With a starting string like this:
string str="\\u5b89\\u5fbd\\";
You don't need any replace to output what you want, if for "output" you mean something like Console or an HTML page...
I am sent an XML string that I'm trying to parse via an XmlReader and I'm trying to strip out the \" characters.
I've tried
.Replace(#"\", "")
.Replace("\\''", "''")
.Replace("\\''", "\"")
plus several other ways.
Any ideas?
Were you trying it like this:
string text = GetTextFromSomewhere();
text.Replace("\\", "");
text.Replace("\"", "");
? If so, that's the problem - Replace doesn't change the original string, it returns a new string with the replacement performed... so you'd want:
string text = GetTextFromSomewhere();
text = text.Replace("\\", "").Replace("\"", "");
Note that this will replace each backslash and each double-quote character; if you only wanted to replace the pair "backslash followed by double-quote" you'd just use:
string text = GetTextFromSomewhere();
text = text.Replace("\\\"", "");
(As mentioned in the comments, this is because strings are immutable in .NET - once you've got a string object somehow, that string will always have the same contents. You can assign a reference to a different string to a variable of course, but that's not actually changing the contents of the existing string.)
In .NET Framework 4 and MVC this is the only representation that worked:
Replace(#"""","")
Using a backslash in whatever combination did not work...
Try it like this:
Replace("\\\"","");
This will replace occurrences of \" with empty string.
Ex:
string t = "\\\"the dog is my friend\\\"";
t = t.Replace("\\\"","");
This will result in:
the dog is my friend
\ => \\ and " => \"
so Replace("\\\"","")
Where do these characters occur? Do you see them if you examine the XML data in, say, notepad? Or do you see them when examining the XML data in the debugger. If it is the latter, they are only escape characters for the " characters, and so part of the actual XML data.
Replace(#"\""", "")
You have to use double-doublequotes to escape double-quotes within a verbatim string.