Why is there an second '\' when I get my path - c#

I'm writting a small program and I want to get the path of an txt file.
I get the path, but there is always a second '\' in the output of the string variable.
For example:
string path = #"C:\Test\Test\Test\";
expected output: 'C:\Test\Test\Test\'
Output during debug: 'C:\\Test\\Test\\Test\\'
The same is when I use:
public static readonly string AppRoot = Path.GetDirectoryName(Assembly.GetEntryAssembly().Location);
When I run my app during DEBUG, the txt file can not be opened, because it steps into the IF part.
Code:
public static readonly string AppRoot = Path . GetDirectoryName (Assembly.GetEntryAssembly().Location);
FileStream fs;
StreamReader sr;
string dateiname = "anleitung.txt";
string ausgabe;
string path = Path.Combine(AppRoot, dateiname);
if (!File.Exists(path))
{
MessageBox.Show("Die Datei '" + dateiname + "' existiert nicht!", "Fehler", MessageBoxButtons.OK,MessageBoxIcon.Error);
return;
}
fs = new FileStream(dateiname, FileMode.Open);
sr = new StreamReader(fs);
ausgabe = "";
while (sr.Peek() != -1)
ausgabe += sr.ReadLine() + "\n";
sr.Close();
The txt file is stored in the project folder.
The WinForms APP is written in C# with .Net Framework 4.8
Maybe anyone has an idea.
Thank you in advance.

The IDE will show you that it has escaped the backslashes by displaying the double backslash. However, the string itself does not actually contain double backslashes.
There is further information about how escaping is defined in C# here.
If you were to use other reserved characters you should see escaping in the IDE as you have seen for the double backslash, but not on the string's actual output.
eg:(backslashes) In IDE - C:\\myfolder\\myfile.txt - Actual string output - C:\myfolder\myfile.txt
eg:(single quote) In IDE - "\'varValueWithSingleQuotes\'" - Actual string output - 'varValueWithSingleQuotes'

A backslash in a string is an escape character so that you can include things like \n (a newline) or \t (a tab). If you want to include an actual backslash in the string you need to escape it with another backslash, i.e. \\
So you would write your string as:
string path = "C:\\Test\\Test\\Test\\";
But in your case you are using a verbatim string literal (the #) which treats escape sequences literally. So in that case you do not need to add the additional backslash in your line of code.

Related

How do I use an illegal character?

public void CreateCertificate()
{
File.Create($"
{#"C:\Users\Director\Documents\TestCertApp\TestSub\" + thisYear +
" Certificates- " + certType + "\""}{myFileName}.ppt", 1 ,
FileOptions.None);
}
So I need the backslash between certype and filename to show it belongs within the folder and not next to. It says its an illegal character but how would I get the file in the folder without it?
Based on the code that you wrote the file path that will be generated is (based on my own substitutions for the variables):
String thisYear = "2019";
String certType = "UnderGrad";
String myFileName = "myfile";
String fileToCreate = $"{#"C:\Users\Director\Documents\TestCertApp\TestSub\" + thisYear + " Certificates- " + certType + "\""}{myFileName}.ppt";
Debug.Print(fileToCreate);
Will give you this output:
C:\Users\Director\Documents\TestCertApp\TestSub\2019 Certificates- UnderGrad"myfile.ppt
If you notice there is a " before the filename part of myfile.ppt - This is where the Illegal Character comes from.
If you use this code fragment to generate the path:
String basePath = #"C:\Users\Director\Documents\TestCertApp\TestSub\";
String certificateFolder = $"{thisYear} Certificates- {certType}";
String correctFilePath = Path.Combine(basePath, certificateFolder, $"{myFileName}.ppt");
Debug.Print(correctFilePath);
This will result in the output of:
C:\Users\Director\Documents\TestCertApp\TestSub\2019 Certificates- UnderGrad\myfile.ppt
This version has a \ where the previous code had a " and is no longer illegal, but conforms to the requirement that you wrote the files being in the folder.
Something else to note:
You may want to use Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments); to get the path to the MyDocuments folder of the user.
Well, the short answer is that you cannot use an illegal character in a path or file name. Otherwise it wouldn't be illegal. :)
But it seems that the problem here is that you though you were adding a backslash (\) character, when really you were adding a double quote (") character. So if everything else is ok, you can just replace "\"" with "\\" and it should work.
Part of the problem is also that you're doing some strange combination of string interpolation, and it makes the code really hard to read.
Instead you can use just string interpolation to simplify your string (I had to use concatenation below to prevent horizontal scrolling, but you could remove it):
string filePath = $#"C:\Users\Director\Documents\TestCertApp\TestSub\{thisYear} " +
$#"Certificates- {certType}\{myFileName}.ppt";
But even better would be to use the Path.Combine method, along with some variables, to make the intent very clear:
var rootDir = #"C:\Users\Director\Documents\TestCertApp\TestSub"
var fileDir = $"{thisYear} Certificates- {certType}"
var fileName = "{myFileName}.ppt";
var filePath = Path.Combine(rootDir, fileDir, fileName);

Having trouble while adding double quotes to a string that is inside a variable in C#?

I am trying to pass a filepath to xcopy command for copying a folder from one location to another( CodedUI using C#).
While doing the same the problems is, I am trying to add double quotes around the path but it's not taking the correct path format.
Code:
string Path = "Some path to folder location";
// Tried all these solutions
Path = '\"' + Path + '\"';
Path = '\"' + Path + '\"';
Path = string.Format("\"{0}\"", Path );
Expected: ""Some path to folder location""
Actual:"\"Some path to folder location"\"
Please help.
In debugger you will see the backslash.
Sent your output to Console and you will see the result is good.
string Path = "Some path to folder location";
Path = "\"" + Path + "\"";
Console.WriteLine(Path);
From what i understand, you want to see
"Some path to folder location"
when you print it. If so, do:
string path = "\"Some path to folder location\"";
or
string path = "Some path to folder location";
var finalString = string.Format("\"{0}\"", path);
Maybe you should try verbatim strings like #"the\path\to\another\location".
This is the best way to write paths without having to struggle with escape codes.
EDIT:
You can use double quotes in a verbatim string:
#"""the\path\to\another\location"""
If you're trying to preserve two sets of double quotes, try building the string like so:
var path = "hello";
var doubleQuotes = "\"\"";
var sb = new StringBuilder(doubleQuotes)
.Append(path)
.Append(doubleQuotes);
Console.WriteLine(sb.ToString()); // ""hello""
Of course, if you want single quotes you simply swap doubleQuotes for singleQuotes = "\""; and get "hello".
To add double quote, you need to add '\' before ' " '.
Note that : if you are having '\' in path, you have to take care of it like below.
if path is "D:\AmitFolder"
string path = #"D:\AmitFolder";
//Or
path = "D:\\AmitFolder"
string str = "\"" + path + "\"";
Console.WriteLine(str);
here str will be "Some path to folder location"
Output:
as in above line we are adding "\"" string as prefix and "\"" as post fix of the main string.
While storing string values if any double quotes are to be added they need to be escaped using backshlash(\). Single quotes are used for character data. The following code should get the output needed.
Path = string.Format("\"{0}\"", Path);
Also I have created a small fiddle here.

C# PadRight Backslash or Frontslash

Trying to get a file path from user via cmd input. Want to make sure that there is a "/" or "\" at the end of the file path. Here is my code:
Console.WriteLine("Please specify file location:");
string fileLocation = #Console.ReadLine();
fileLocation = fileLocation.PadRight(1, '/');
However when testing it doesn't seem to add the character. What is wrong? Is there a better way to do this?
Thanks!
I don't think that you actually want to use PadRight
Returns a new string of a specified length in which the end of the current string is padded with spaces or with a specified Unicode character.
What about just checking for it and appending it to the end of the string if it doesnt exist instead:
if(!fileLocation.EndsWith("/"))
{
fileLocation += "/";
}

Write Tab Delimited File

I'm having trouble writing a Tab-delimited File and I've checked around here and have not gotten my answers yet.
So I've got a function that returns the string with the important pieces below (delimiter used and how I build each line):
var delimiter = #"\t";
sb.Append(string.Join(delimiter, itemContent));
sb.Append(Environment.NewLine);
The string returned is like this:
H\t13\t170000000000001\t20150630
D\t1050\t10.0000\tY
D\t1050\t5.0000\tN
And then I write it to a file with this (content below is the string above):
var content = BuildFile(item);
var filePath = tempDirectory + fileName;
// Create the File
using (FileStream fs = File.Create(filePath))
{
Byte[] info = new UTF8Encoding(true).GetBytes(content);
fs.Write(info, 0, info.Length);
}
However, the file output is this with no tabs (opened in notepad++):
H\t13\t170000000000005\t20150630
D\t1050\t20.0000\tN
D\t1050\t2.5000\tY
When it should be more like this (sample file provided):
H 100115980 300010000000003 20150625
D 430181 1 N
D 342130 2 N
D 459961 1 N
Could this be caused by the encoding I used? Appreciate any input you may have, thanks!
Using var delimiter = #"\t";, the variable contains a literal \ plus t. The # syntax disables the backslash as "special". In this case you really want
var delimiter = "\t";
to have a tab character.
There is a typo in your code. The # prefix means that the following string is a literal so #"\t" is a two-character string with the characters \ and t
You should use "\t" without the prefix.
You should consider using a StreamWriter instead of constructing the entire string in memory and writing the raw bytes though. StreamWriter uses UTF-8 by default and allows you to write formatted lines just as you would with Console.WriteLine:
var delimiter ="\t";
using(var writer=new StreamWriter(filePath))
{
var line=string.Join(delimiter, itemContent);
writer.WriteLine(line);
}

Does System.IO.File.Move not support previously-defined strings?

For example, something like this fails:
string oldfile = (#"C:\oldfile.txt");
string newfile = (#"C:\newfolder\newfile.txt");
System.IO.File.Move(oldfile, newfile);
Program crashes with "The given path's format is not supported."
EDIT: I'm doing this in a Windows Forms project vs. Console project, does that make a difference? Intuitively I wouldn't think it should, but you never know...
The problem is the mixture of the verbatim string format ( #"..." ) and escaping slashes ( "\" )
The second piece of code
string oldFile = #"C:\\oldfile.txt"
creates a path of 'C:\\oldfile.txt' which is not recognised as a valid path.
Either use the first version you gave
string oldFile = #"C:\oldfile.txt"
or
string oldFile = "C:\\oldfile.txt"
string oldfile = (#"C:\oldfile.txt");
string newfile = (#"C:\newfolder\newfile.txt");
System.IO.File.Move(oldfile , newfile );
or
string oldfile = ("C:\oldfile.txt");
string newfile = (#"C:\newfolder\newfile.txt");
System.IO.File.Move(oldfile , newfile );
if the direcotry not exist, create it with Directory.CreateDirectory
In a string literal prefixed with # the escape sequences starting with \ are disabled. This is convenient for filepaths since \ is the path separator and you don't want it to start an escape sequence.
You simply have to use the below one:
string oldfile = ("C:\\oldfile.txt");
string newfile = ("C:\\newfolder\\newfile.txt");
System.IO.File.Move(oldfile, newfile);
OR
string oldfile = (#"C:\oldfile.txt");
string newfile = (#"C:\newfolder\newfile.txt");
System.IO.File.Move(oldfile, newfile);
It works without crash.
Refer this MSDN Article
MSDN says to use like this
string path = #"C:\oldfile.txt";
string path2 = #"C:\newfolder\newfile.txt";
if (!File.Exists(path))
{
// This statement ensures that the file is created,
// but the handle is not kept.
using (FileStream fs = File.Create(path)) {}
}

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