i'm having a problem with encoding in c#
i'm downloading an xml file encoded in windows-1250 and then, when saved to a file, special characters like Š and Đ are replaced with ? even tho the file is saved correctly using the windows-1250 encoding.
this is an example of my code (simplified):
var res = Encoding.GetEncoding("Windows-1250").GetBytes(client.DownloadString("http://link/file.xml"));
var result = Encoding.GetEncoding("Windows-1250").GetString(res);
File.AppendAllText("file.xml", result);
the xml file is in fact encoded using windows-1250 and it reads just fine when i download it using the browser.
anyone knows what's going on here?
The problem could result from two different sources, one at the beginning and one at the end of your snippet.
And as has been pointed out, the Encoding and Decoding you are doing in your code is actually useless, because the origin (what DownloadString returns) and target (the variable result) are both C# Unicode strings.
Source 1: DownloadString
DownloadString could not properly decode the Windows-1250 encoded string, because either the server did not send the correct charset in the Content-Type header, or DownloadString doesn't even support this (unlikely, but I'm not familiar with DownloadString).
Source 2: File.AppendAllText
The string was downloaded correctly, then encoded in memory to Windows-1250, then decoded to a Unicode string again and everything worked well.
But then it was written by File.AppendAllText in another default encoding. AppendAllText has an optional, third parameter that you can use to specify the encoding. You should set this to Windows-1250 to actually write a file in Windows-1250 encoding.
Also, make sure that whatever editor you use to open the file uses the same encoding - this is often not very easy to guarantee, so I'd suggest you open it in a "developer-friendly" editor that lets you specify the encoding when opening a text file. (Vim, Emacs, Notepad++, Visual Studio, ...).
Related
In a C# console app, I am using stringbuilder to write data to a local file. It seems to be mishandling special characters
Muñoz
outputs to the file as
Muñoz
at a bit of a loss how to manage that correctly.
Your C# code is correctly writing a UTF8 file, in which ñ is encoded as 3 bytes.
You're incorrectly reading the file as a different encoding which shows those bytes as three unwanted characters.
You need to read the file as UTF8.
I have a C++ program that sends data via FTP via ASCII mode to an IBM Mainframe. I am now doing this via C#.
When it gets there and viewed the file looks like garbage.
I cannot see anything in the C++ code that does anything special to encode the file into something like EPCDIC. When the C++ files are sent they are viewed ok. The only thing I see different is \015 & \012 for line feeds whereas C# is using \r\n.
Would these characters have an effect and if so how can I get my C# app to use \015?
Do I have to do any special encoding to make it appear ok?
It sounds like you should indeed be using an EBCDIC encoding, and then probably transferring the text in binary. I have an EBCDIC encoding class you can use, should you wish.
Note that \015\012 is \r\n - they're characters 13 and 10 in decimal, just different ways of representing them. If you think the C++ code really is producing the same files as C#, compare two files which should be the same in a binary file editor.
Make sure you have the TYPE TEXT instead of TYPE BINARY command before you transfer the file.
If you are truly sending the files in ASCII mode, then the mainframe itself will convert that to EBCDIC (it's receiver-makes-good).
The fact that you're getting apparent garbage at the mainframe end, and character codes \015 and \012 (which are CR and LF respectively) means that you're not transferring in ASCII mode.
As an aside, the ISPF editor has been able to view ASCII data sets for quite a few versions now. Open up the file and enter the commands source ascii and lf.
The first renders converts the characters from ASCII to EBCDIC so you can see what they are, the second goes through and pads out "lines" so that linefeed markers are replaced with enough spaces to reach the record length.
Invaluable commands when dealing with mixed-encoding environments, which is where I do a lot of my work.
I'm having an issue with a simple C# program that is meant to read an XML document from the web, pull out some elements, and then write the contents of those elements to an HTML file (in a simple table). Though the XML documents are correctly encoded as UTF-8, in the end, all of my generated HTML files are failing to correctly transcribe non-Western English characters (e.g. "Wingdings"-like output when parsing Japanese).
Since the XML files are really large, the program works by having an XmlReader yielding matching elements as it encounters them, which are then written to the HTML file using a StreamWriter.
Does anyone have a sense of where in a program like this the UTF-8 encoding might have to be explicitly forced?
The short explanation
I'm going to guess here: Your browser is displaying the page using the wrong character encoding.
You need to answer: What character encoding does your browser think the HTML is? (I bet it's not UTF-8.)
Try to adjust your browser: for example, in Firefox, this is View → Character Encoding, then select the character encoding to match your document.
Since you seem to have a very multilingual document, have your C# output in UTF-8 - which supports every character known to man, including Japanese, Chinese, Latin, etc. Then try to tell Firefox, IE, whatever, to use UTF-8. Your document should display.
If this is the problem, the you need to inform the browser of the encoding of your document. Do so by (see this):
Having your web server return the character encoding in the HTTP headers.
Specifying a character encoding in a <meta> tag.
Specifying a character encoding in the XML preamble for XHTML.
The more of those you do, the merrier.
The long explanation
Let's have a look at a few things you mentioned:
using (StreamWriter sw = new StreamWriter(outputFile,true,System.Text.Encoding.UTF8))
and
found that using Text.Encoding.Default made other Western character sets with accents work (Spanish accents, German umlauts), although Japanese still exhibits problems.
I'm going to go out on a limb, and say that you're an American computer user. Thus, for you, the "default" encoding on Windows is probably Windows-1252. The default encoding that a web browser will use, if it can't detect the encoding on an HTML document, is ISO-8859-1. ISO-8859-1 and Windows-1252 are very similar, and they both display ASCII plus some common Latin characters such as é, è, etc. More importantly, the accented characters are encoded the same, so, for those characters, the two encodings will both decode the same data. Thus, when you switched to "default", the browser was correctly decoding your Latin characters, albeit with the wrong encoding. Japanese doesn't exist in either ISO-8859-1 or Windows-1252, and both of those will result in Japanese just appears as random characters. ("Mojibake")
The fact that you noted that switching to "default" fixes some of the accented latin characters tells me that your browser is using ISO-8859-1, which isn't what we want: We want to encode the text using UTF-8, and we need the browser to read it back as such. See the short explanation for the how to do that.
I'm reading a CSV file with Fast CSV Reader (on codeproject). When I print the content of the fields, the console show the character '?' in some words. How can fix it?
The short version is that you have to know the encoding of any text file you're going to read up front. You could use things like byte order marks and other heuristics if you really aren't going to know, but you should always allow for the value to be tweaked (in the same way that Excel does if you're importing CSV).
It's also worth double checking the values in the debugger, as it may be that it is the output that is wrong, as opposed to the reading -- bear in mind that all strings are Unicode internally, and conversion to '?' sounds like it is failing converting the unicode to the relevant code page for the console.
I've got a FileUpload control in an ASP.NET web page which is used to upload a file, the contents of which (in a stream) are processed in the C# code behind and output on the page later, using HtmlEncode.
But, some of this output is becoming mangled, specifically the symbol '£' is output as the Unicode FFFD REPLACEMENT CHARACTER. I've tracked this down to the input file, which is Windows 1252 ('ANSI') encoded.
The question is,
How do I determine whether the file is encoded as 1252 or UTF8? It could be either, and
How do I convert it to UTF8 if it is in Windows 1252, preserving the symbol £ etc?
I've looked online but cannot find a satisfactory answer.
If you know that the file is encoded with Windows 1252, you can open the file with a StreamReader and pass the proper encoding. That is:
StreamReader reader = new StreamReader("filename", Encoding.GetEncoding("Windows-1252"), true);
The "true" tells it to set the encoding based on the byte order marks at the front of the file, if they're there. Otherwise it opens it as Windows-1252.
You can then read the file and, if you want to convert to UTF-8, write to a file that you've opened with that endcoding.
The short answer to your first question is that there isn't a 100% satisfactory way to determine the encoding of a file. If there are byte order marks, you can determine what flavor of Unicode it is, but without the BOM, you're stuck with using heuristics to determine the encoding.
I don't have a good reference for the heuristics. You might search for "how does Notepad determine the character set". I recall seeing something about that some time ago.
In practice, I've found the following to work for most of what I do:
StreamReader reader = new StreamReader("filename", Encoding.Default, true);
Most of the files I read are those that I create with .NET's StreamWriter, and they're in UTF-8 with the BOM. Other files that I get are typically written with some tool that doesn't understand Unicode or code pages, and I just treat it as a stream of bytes, which Encoding.Default does well.