How do I read hex sequences like xD0 into a C# string? - c#

I am converting a series of strings that are designed to display correctly using a special font into a unicode version that can be used anywhere. It's just a glorified set of string replaces:
"e]" -> "ἓ"
etc.
I'm reading the text using a streamreader which takes the encoding to be UTF-8. All working well. But there are some characters used to replace the punctuation marks that just aren't working. I can see them as hex sequences in notepad++ (encoding set to UTF-8) but when I read them, they all get reduced down to the same character (the 'cannot display' question mark in the black diamond).
StreamReader srnorm = new StreamReader("C:\\Users\\John\\Desktop\\bgt.txt", Encoding.UTF8);
string norm = srnorm.ReadLine();
Should I be reading it as a binary file and working from there or is my encoding very wrong?
(Full size image)
When I read that, I get the following:
o]j ouvci. mh. �avpo�la,bh| pollaplasi,ona evn tw/| kairw/| tou,tw| kai. evn tw/| aivw/ni tw/| evrcome,nw| zwh.n aivw,nion�

C# strings use UTF-16. This is how they are stored in memory. Because of this you should be able to read the string into memory and replace the characters without any issues. You can then write those characters back to a file (UTF8 is the default character encoding for reading and writing to file if I'm not mistaken). The ?'s just means the console you outputed the string to does not support those characters or the bytes are not of a valid encoding.
Here is a good article by Jon Skeet about C#/.NET strings.

Related

Read multiple files with different encoding, preserving all characters

I am trying to read a text file and writing to a new text file. The input file could be ANSI or UTF-8. I don't care what the output encoding is but I want to preserve all characters when writing. How to do this? Do I need to get the input file's encoding (seems like alot of work).
The following code reads ANSI file and writes output as UTF-8 but there is some gibberish characters "�".
I am looking for a way to read the file no matter which of the 2 encoding and write it correctly without knowing the encoding of input file before hand.
File.WriteAllText(outputfile,File.ReadAllText(inputfilepath + #"\ST60_0.csv"));
Note that this batch command reads a UTF-8 and ANSI file and writes the output as ANSI with all chars preserved so I'm looking to do this but in C#:
type ST60_0.csv inputUTF.csv > outputBASH.txt
Q: The following code reads ANSI file and writes output as UTF-8 but
there is some giberrish characters "�".
A: It would definitely be useful to see the hex values of some of these "gibberish" characters. Perhaps you could install a Hex plugin to Notepad++ and tell us?
Q: It blows my mind its so hard to do something in C# that command
prompt can do easy
A: Typically, it IS easy. There seems to be "something special" written into this particular file.
The difference between C# and other, "simpler" approaches is that C# (unlike C character I/O or .bat files) gives you the flexibility to deal with text that doesn't happen to be "standard ASCII".
ANYWAY:
If "?" you posted (hex 0xefbfbd) is a valid example of your actual text, this might explain what's going on:
https://stackoverflow.com/a/25510366/421195
... %EF%BF%BD is the url-encoded version of the hex representation of
the 3 bytes (EF BF BD) of the UTF-8 replacement character.
See also:
https://en.wikipedia.org/wiki/Specials_(Unicode_block)
The Replacement character � (often displayed as a black rhombus with a
white question mark) is a symbol found in the Unicode standard at code
point U+FFFD in the Specials table. It is used to indicate problems
when a system is unable to render a stream of data to a correct
symbol.[4] It is usually seen when the data is invalid and does not
match any character
You might also be interested in this:
https://learn.microsoft.com/en-us/dotnet/standard/base-types/character-encoding
Best-Fit Fallback When a character does not have an exact match in the target encoding, the encoder can try to map it to a similar
character.
UPDATE:
The offending character was "»", hex 0xc2bb. This is a "Right Angle Quote", a Guillemet. Angle quotes are the quotation marks used in certain languages with an otherwise roman alphabet, such as French.
One possible solution is to specify "iso-8859-1", vs. the default encoding "UTF-8":
File.WriteAllText(outputfile,File.ReadAllText(inputfilepath + #"\ST60_0.csv", System.Text.Encoding.GetEncoding("iso-8859-1")));

Encoding "œ" with iso-8859-1 in C#

I am using below code to read a CSV file:
using (StreamReader readfile = new StreamReader(FilePath, Encoding.GetEncoding("iso-8859-1")))
{
// some code will go here
}
There is a character œin a column of the CSV file. Which is getting converted to ? in output. How can i get this œ encoded correctly so that in output i will get same œ character not a question mark.
This is an encoding problem. Many non-Unicode encodings are either incomplete and translate many characters to "?", or have subtly different behavior on different platforms. Consider using UTF-8 or UTF-16 as the default. At least, if you can.
"windows-1252" is a superset of "ISO-8859-1". Try with Encoding.GetEncoding(1252).
Demo:
public static void Main()
{
System.IO.File.AppendAllText("test","œ", System.Text.Encoding.GetEncoding(1252));
var content = System.IO.File.ReadAllText("test", System.Text.Encoding.GetEncoding(1252));
Console.WriteLine(content);
}
Try it online!
The iso-8859-15 character set contain those symbols, as does the Windows-1252 codepage. However, be aware that 8859-15 redefines six other RARELY USED (or ASCII duplicate) chars that are in 8859-1, but so does Windows 1252. A quick web search will reveal those differences.

Change encoding to UTF8 for data kept in base64string

I need to process CSV files that are kept as bsae64strings. I never know in what format they were created (usually it'll be ANSI or UTF-8). I have been struggling to achieve anything useful, still, I receive messed up characters when I am testing my code on CSV file that was saved in ANSI. The code to read is just a two-liner:
byte[] dataToDecode = Convert.FromBase64String(base64Content);
string csvContentInUTF8 = Encoding.UTF8.GetString(dataToDecode2);
I do not have access to the code that saves files.
Sample line that's in the input CSV:
;;;superÆ/æ Ø/ø and even Å/å Topic;;John;Doe;;;;john#doe.com;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
what I get after decoding (second line of code)
;;;super�/� �/� oraz �/� Topic;;John;Doe;;;;john#doe.com;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
following this question I tried changing the code to scandinavian encoding reading, so:
string csvContentInUTF8x = Encoding.GetEncoding("iso-8859-1").GetString(dataToDecode);
The output is:
;;;super�/� �/� oraz �/� Topic;;John;Doe;;;;john#doe.com;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
It looks exactly the same for the Encoding.Default
If what you wrote is correct, the text was corrupted before writing it in a csv file.
Now... Encoding.GetEncoding("iso-8859-1") is an identical encoding that doesn't do any remapping. Its 256 characters are mapped 1:1 to the first 256 (0-255) characters of unicode.
;;;super�/� �/� oraz �/� Topic;;John;Doe;;;;john#doe.com
You see the � repeated six times? Normally each time it should be different, because you want six different characters (Æ/æ, Ø/ø, Å/å). But here they are always the same. And this is because in UTF-8 � is the Unicode REPLACEMENT CHARACTER � that is used when a character can't be encoded. So the error is already present in your dataToDecode.

How to read and store string in UTF-8 format in C#?

I have a file with URLs, one of which is http://en.wikipedia.org/wiki/São_Paulo. Note that 'ã'. When I read the URLs (in C#) and try to print it, it appears as http://en.wikipedia.org/wiki/S?o_Paulo.
I tried reading the URLs as following:
List<string> urls = System.IO.File.ReadAllLines(wikiURL_FilePath, Encoding.UTF8).ToList();
Note that I have passed second argument to read it in UTF8 format, but still the problem is not rectified. How can I read and store the string in correct form?
The data you have shown is simply not UTF-8, despite having a UTF-8 BOM; the UTF-8 for São is 53-C3-A3-6F; you have 53-E3-6F, which is... the right unicode code-points for basic multi-lingual plane data, but incorrectly encoded to disk as UTF-8. You probably need to fix the code that wrote this file, or: agree on what the encoding is (it could be a single-byte code-page, but you need to agree which, else everything falls apart).
Likely looking encodings (if we take away the BOM):
utf-7
windows-1252
windows-1254
iso-8859-1
iso-8859-4
iso-8859-9
iso-8859-15

ansi to unicode conversion

While parsing certain documents, I get the character code 146, which is actually an ANSI number. While writing the char to text file, nothing is shown. If we write the char as Unicode number- 8217, the character is displayed fine.
Can anyone give me advice on how to convert the ANSI number 146 to Unicode 8217 in C#.
reference: http://www.alanwood.net/demos/ansi.html
Thanks
"ANSI" is really a misnomer - there are many encodings often known as "ANSI". However, if you're sure you need code page 1252, you can use:
Encoding encoding = Encoding.GetEncoding(1252);
using (TextReader reader = File.OpenText(filename, encoding))
{
// Read text and use it
}
or
Encoding encoding = Encoding.GetEncoding(1252);
string text = File.ReadAllText(filename, encoding);
That's for reading a file - writing a file is the same idea. Basically when you're converting from binary (e.g. file contents) to text, use an appropriate Encoding object.
My recommendation would be to read Joel's "Absolute Minimum Every Software Developer Must Know About Unicode and Character Sets. There's quite a lot involved in your question and my experience has been that you'll just struggle against the simple answers if you don't understand these basics. It takes around 15 minutes to read.

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