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c# UTF8 GetString from bytes array not equal to php chr function

I'm trying to make one decoder. Basic system .Net 4.7 I'm trying to migrate this system into php, but I'm having trouble converting bytes. As far as I understand the default string UTF-16le on C#, I understood the ord and chr functions as UCS-2 on the PHP side. I want to do below and I do not get the same result there are codes. What can I do to fix this, thanks in advance
XOR Encoded Text Bytes = [101,107,217,78,40,68,234,218,162,67,139,81,44,166,24,148];
on C#
string result = System.Text.Encoding.UTF8.GetString(destinationArray);
On PHP
for($i=0;$i<sizeof($encoded);$i++){
echo "\t".$encoded[$i]." => ".chr($encoded[$i])."\n";
$tmpStr .= chr($encoded[$i]);
}
C# Result size=26:
ek�N(D�ڢC�Q,��
PHP Result size=16:
ek�N(D�ڢC�Q,��
the strings looks the same, but byte translation is quite different.
C# Result to Bytes array:
byte[] utf8 = System.Text.Encoding.Unicode.GetBytes(result);
Console.WriteLine(string.Join("-", utf8));
response =
101-0-107-0-253-255-78-0-40-0-68-0-253-255-162-6-67-0-253-255-81-0-44-0-253-255-24-0-253-255
PHP Result to Bytes Array:
echo implode("-",unpack("C*", $tmpStr));
response = 101-107-217-78-40-68-234-218-162-67-139-81-44-166-24-148
if php response convert to UTF-16le, results again different
echo implode("-",unpack("C*", mb_convert_encoding($tmpStr,'UTF-16le')));
response =
101-0-107-0-63-0-78-0-40-0-68-0-63-0-162-6-67-0-63-0-81-0-44-0-63-0-24-0-63-0

You are mixing quite different things here.
First, in the C# code, you are not using the same encoding when converting from bytes to a string and then from a string back to bytes: Encoding.UTF8 in the first case and Encoding.Unicode (which is .NET name for UTF-16) in the latter... Things cannot go well if you do this. And by the way, I'm not sure that PHP's UCS2 is equivalent to UTF-16:
UTF-8 encodes characters on 1, 2, 3 or 4 bytes depending on the character
UTF-16 encodes characters on 2 or 4 bytes depending on the character
UCS-2 always encodes characters on 2 bytes, and hence cannot encode more than 65536 characters...
Then what you pass to the 'bytes to string' conversions is not necessarily valid! Because you've XORed the input data (I assume it to be some secret string), the resulting bytes may or may not be a valid sequence in some encodings. For example:
It is not valid in ASCII because you have (in your example) bytes > 127
It is not valid in UTF-8 because 217 followed by 78 is recognized neither as a 1-, 2-, 3-, or 4-byte character by UTF-8; hence, the � you see before the N.
It seems to be invalid UTF-16 as well, but roundtripping works (I could get back the original array using .NET's Unicode.GetString, then Unicode.GetBytes. If I remove your last byte - and end up with an odd number of bytes - then UTF-16 roundtripping does not work any more...
Although I did not test it, it should also be invalid UCS-2 because UCS-2 'looks like' UTF-16 for 2-byte characters.
Roundtripping works with ANSI encodings sucha as windows-1252 because these encodings accept any byte. However, I would discourage using such trick because you have to be sure the same code page is used on both sides of the encoding/decoding process.
Therefore, I think, in your case, the best way to store your XORed bytes into a string would be to convert the array to base64. In C# you can do it this way:
// The code below gives you ZWt1TihEInY+QydRLEIYMA==
var converted = Convert.ToBase64String(array);
// And this one gives you back the initial array
var bytes = Convert.FromBase64String(converted);
Quick googling will tell you to use base64_encode and base64_decode in PHP.
Bottom note: if you want to really understand what's going on with al this encodings stuff, here is the must-read blog post on the subject: https://www.joelonsoftware.com/2003/10/08/the-absolute-minimum-every-software-developer-absolutely-positively-must-know-about-unicode-and-character-sets-no-excuses/

UTF-8 Encoding and Decoding in c#

I Searched for " How to Encode the data in utf-8 format". Regarding this I got the best result is following:
UTF8Encoding utf8 = new UTF8Encoding();
String unicodeString = "ABCD";
// Encode the string.
Byte[] encodedBytes = utf8.GetBytes(unicodeString);
// Decode bytes back to string.
String decodedString = utf8.GetString(encodedBytes);
But the Problem is when I see the encoded data I found that is not more than ASCII code.
can any one help me to improve my knowledge.
For example as I passed "ABCD " it gets converted into 65,66,67,68.... I think this is not utf-8

UTF-8 is backwards compatible with ASCII of course. You should test with some characters that are not included in ASCII.
If you program in C# the strings are already encoded in UTF-16. You will not see anything Special there. If you want to see something you should try to compare the LENGTH of the Byte[] when you encode the string into different Encodings.

Check out the Wikipedia article on UTF8: Wikipedia.
From there:
Backward compatibility: One-byte codes are used only for the ASCII
values 0 through 127. In this case the UTF-8 code has the same value
as the ASCII code. The high-order bit of these codes is always 0. This
means that UTF-8 can be used for parsers expecting 8-bit extended
ASCII even if they are not designed for UTF-8.
The point here is that for anything that would be ASCII 0-127 in UTF8 it's the same. You need to try more extended characters (an example in the article is the Euro symbol) to see how it's different. Or try an ASCII value greater than 127 and you'll see it different.

Handle Non-UTF-8 Characters in Byte Array

I have an array of bytes which contains some characters that are not UTF-8. These characters cannot be deserialized using UTF-8 encoding. So, my question is, how can I handle these characters and make the string readable in whatever language it is.
For example, if I have an array:
byte[] b = myArrayWithNonUTF8Characters;
And I try to deserialize the array with:
DataContractJsonSerializer jsonSerializer = new DataContractJsonSerializer(typeof(MyObject));
MyObject objResponse = (MyObject)jsonSerializer.ReadObject(new MemoryStream(b));
Then I get an error that the array contains invalid UTF8 bytes.
Any way to make this work?
PS: Please, do not give me this answer: string s = System.Text.Encoding.UTF8.GetString(b, 0, b.Length); It will only return symbols replacing the non-UTF-8 characters.

The beauty of UTF is that it encodes characters in most languages; so you can have Greek and Japanese in the same character stream.
Without UTF, your entire stream (or in your case an array) must be in a single language defined by a Code Page. Each character is represented by an ASCII byte but the actual character is determined by the Code Page (see http://en.wikipedia.org/wiki/Code_page for more details).
For example if your text was written in Greek you might use Code Page 111:
System.Text.Encoding.GetEncoding(111)
In short, you need to know what language the ASCII text was written in.

A weird thing in c# Encoding

I convert a byte array to a string , and I convert this string to byte array.
these two byte arrays are different.
As below:
byte[] tmp = Encoding.ASCII.GetBytes(Encoding.ASCII.GetString(b));
Suppose b is a byte array.
b[0]=3, b[1]=188, b[2]=2 //decimal system
Result:
tmp[0]=3, tmp[1]=63, tmp[2]=2
So that's my problem, what's wrong with it?

188 is out of range for ASCII. Characters that are not in the corresponding character set are transposed to '?' by design (would you prefer transposing to "1/4"?)

ASCII is 7-bit only, so others are invalid. By default it uses ? to replace any invalid bytes and that's why you get a ?.
For 8-bit character sets, you should be looking for either the Extended ASCII (which is later defined "ISO 8859-1") or the code page 437 (which is often confused with Extended ASCII, but in fact it's not).
You can use the following code:
Encoding enc = Encoding.GetEncoding("iso-8859-1");
// For CP437, use Encoding.GetEncoding(437)
byte[] tmp = enc.GetBytes(enc.GetString(b));

The character 188 is not defined for ASCII. Instead, you're getting 63, which is a question mark.

The ASCII character set has a range from 1 to 127. You can see 188 is not in this range and is converted to ? (= ASC 63).

Not every sequence of bytes is necessarily a valid sequence of encoded values for a particular encoding.
So the result of Encoding.ASCII.GetString(b) on an arbitrary array of bytes, b, is poorly defined. (And could be, for any other encoding also).
If you need to take an arbitrary byte array and obtain a sequence of characters, you might want to look into the Convert classes ToBase64String and FromBase64String. If that's not what you're trying to do, maybe explain the original problem to us.

188 isn't in the range of ASCII (7 bit), you should use Encoding.Default to get the ANSI encoding:
byte[] b = new byte[3]{ 3, 188, 2 };
byte[] tmp = Encoding.Default.GetBytes(Encoding.Default.GetString(b));

Can we simplify this string encoding code

Is it possible to simplify this code into a cleaner/faster form?
StringBuilder builder = new StringBuilder();
var encoding = Encoding.GetEncoding(936);
// convert the text into a byte array
byte[] source = Encoding.Unicode.GetBytes(text);
// convert that byte array to the new codepage.
byte[] converted = Encoding.Convert(Encoding.Unicode, encoding, source);
// take multi-byte characters and encode them as separate ascii characters
foreach (byte b in converted)
builder.Append((char)b);
// return the result
string result = builder.ToString();
Simply put, it takes a string with Chinese characters such as 鄆 and converts them to ài.
For example, that Chinese character in decimal is 37126 or 0x9106 in hex.
See http://unicodelookup.com/#0x9106/1
Converted to a byte array, we get [145, 6] (145 * 256 + 6 = 37126). When encoded in CodePage 936 (simplified chinese), we get [224, 105]. If we break this byte array down into individual characters, we 224=e0=à and 105=69=i in unicode.
See http://unicodelookup.com/#0x00e0/1
and
http://unicodelookup.com/#0x0069/1
Thus, we're doing an encoding conversion and ensuring that all characters in our output Unicode string can be represented using at most two bytes.
Update: I need this final representation because this is the format my receipt printer is accepting. Took me forever to figure it out! :) Since I'm not an encoding expert, I'm looking for simpler or faster code, but the output must remain the same.
Update (Cleaner version):
return Encoding.GetEncoding("ISO-8859-1").GetString(Encoding.GetEncoding(936).GetBytes(text));

Well, for one, you don't need to convert the "built-in" string representation to a byte array before calling Encoding.Convert.
You could just do:
byte[] converted = Encoding.GetEncoding(936).GetBytes(text);
To then reconstruct a string from that byte array whereby the char values directly map to the bytes, you could do...
static string MangleTextForReceiptPrinter(string text) {
return new string(
Encoding.GetEncoding(936)
.GetBytes(text)
.Select(b => (char) b)
.ToArray());
}
I wouldn't worry too much about efficiency; how many MB/sec are you going to print on a receipt printer anyhow?
Joe pointed out that there's an encoding that directly maps byte values 0-255 to code points, and it's age-old Latin1, which allows us to shorten the function to...
return Encoding.GetEncoding("Latin1").GetString(
Encoding.GetEncoding(936).GetBytes(text)
);
By the way, if this is a buggy windows-only API (which it is, by the looks of it), you might be dealing with codepage 1252 instead (which is almost identical). You might try reflector to see what it's doing with your System.String before it sends it over the wire.

Almost anything would be cleaner than this - you're really abusing text here, IMO. You're trying to represent effectively opaque binary data (the encoded text) as text data... so you'll potentially get things like bell characters, escapes etc.
The normal way of encoding opaque binary data in text is base64, so you could use:
return Convert.ToBase64String(Encoding.GetEncoding(936).GetBytes(text));
The resulting text will be entirely ASCII, which is much less likely to cause you hassle.
EDIT: If you need that output, I would strongly recommend that you represent it as a byte array instead of as a string... pass it around as a byte array from that point onwards, so you're not tempted to perform string operations on it.

Does your receipt printer have an API that accepts a byte array rather than a string?
If so you may be able to simplify the code to a single conversion, from a Unicode string to a byte array using the encoding used by the receipt printer.
Also, if you want to convert an array of bytes to a string whose character values correspond 1-1 to the values of the bytes, you can use the code page 28591 aka Latin1 aka ISO-8859-1.
I.e., the following
foreach (byte b in converted)
builder.Append((char)b);
string result = builder.ToString();
can be replaced by:
// All three of the following are equivalent
// string result = Encoding.GetEncoding(28591).GetString(converted);
// string result = Encoding.GetEncoding("ISO-8859-1").GetString(converted);
string result = Encoding.GetEncoding("Latin1").GetString(converted);
Latin1 is a useful encoding when you want to encode binary data in a string, e.g. to send through a serial port.