Develop Reference

Byte array read from a file and byte array converted from string read from same file differs

If i read byte array from a file and write it using below code
byte[] bytes = File.ReadAllBytes(filePath);
File.WriteAllBytes(filePath, byteArr);
works perfectly fine.I can open and view the written file properly.
But if i read file contents into a string and then convert it to byte array using below function
string s = File.ReadAllText(filePath);
var byteArr = System.Text.Encoding.UTF8.GetBytes(s);
the size of byte array is more than the previous array read directly from file and the values are also different, hence if i write the file using this array the cannot be read when opened
Note:- File is utf-8 encoded
i found out that using below code
using (StreamReader reader = new StreamReader(filePath, Encoding.UTF8, true))
{
reader.Peek(); // you need this!
var encoding = reader.CurrentEncoding;
}
Unable to understand why both the array differs??
I was using the below attached image for converting and then writing

With
using (StreamReader reader = new StreamReader(filePath, Encoding.UTF8, true))
{
reader.Peek(); // you need this!
var encoding = reader.CurrentEncoding;
}
your var encoding will just echo the Encoding.UTF8 parameter. You are deceiving yourself there.
A binary file just has no text encoding.
Need to save a file may be anything an image or a text
Then just use ReadAllBytes/WriteAllBytes. A text file is always also a byte[], but not all file types are text. You would need Base64 encoding first and that just adds to the size.

The safest way to convert byte arrays to strings is indeed encoding it in something like base64.
Like:
string s= Convert.ToBase64String(bytes);
byte[] bytes = Convert.FromBase64String(s);

How to insert List<> values into SQL Binary field using C#

I'm not entirely new to programming but I still see myself as a novice. I'm currently creating an Invoicing system with a max of 5 line items, this being said, I'm creating a String<> item, serializing it to store and then de-serializing it to display.
So far I've managed the serializing, and de-serializing, and from the de-serialized value I've managed to display the relevant information in the correct fields.
My question comes to: HOW do I add the list of items in the String<> object to either a Binary or XML field in my SQL table?
I know it should be similar to adding an Image object to binary but there's a catch there. usually:
byte[] convertToByte(string sourcePath)
{
//get the byte file size of image
FileInfo fInfo = new FileInfo(sourcePath);
long byteSize = fInfo.Length;
//read the file using file stream
FileStream fStream = new FileStream(sourcePath, FileMode.Open, FileAccess.Read);
//read again as byte using binary reader
BinaryReader binRead = new BinaryReader(fStream);
//convert image to byte (already)
byte[] data = binRead.ReadBytes((int)byteSize);
return data;
}
this kind of thing is done for an image however the whole "long" thing does not apply to the List<> object.
Any assistance would be helpful

If you simply want to store your data as "readable" text, you can use the varchar(MAX) or nvarchar(MAX) (depending on whether you need extended character support). That translates directly into a string in ADO.NET or EntityFramework.
If all you need are bytes from a string, the Encoding class will do that:
System.Text.Encoding.Default.GetBytes(yourstring);
See: http://msdn.microsoft.com/en-us/library/ds4kkd55%28v=vs.110%29.aspx

A way of saving a binary file in a string is to convert the image to a Base64 string. This can be done with the Convert.ToBase64String (Byte[]) method:
Convert.ToBase64String msdn
string convertImageToBase64(string sourcePath)
{
//get the byte file size of image
FileInfo fInfo = new FileInfo(sourcePath);
long byteSize = fInfo.Length;
//read the file using file stream
FileStream fStream = new FileStream(sourcePath, FileMode.Open, FileAccess.Read);
//read again as byte using binary reader
BinaryReader binRead = new BinaryReader(fStream);
//convert image to byte (already)
byte[] data = binRead.ReadBytes((int)byteSize);
return Convert.ToBase64String (data);
}
Now you will be able to save the Base64 string in a string field in your database.

using Stream writer to Write a specific bytes to textfile

Well I'm trying to write some values and strings to a text file.
but this text file must contain 2 bytes
These are the 2 bytes I want to insert to my text file after finishing writing the other values to it:
I tried this method but I have no idea how to write bytes through it
using (StreamWriter sw = new StreamWriter(outputFilePath, false, Encoding.UTF8))
I have no idea about how to write them to the text file after putting the strings I want on it.

I just figured this out. It works quite well for me. The idea is you open the file with a FileStream that can write byte arrays, and put a StreamWriter on top of it to write strings. And then you can use both to mix strings with your bytes:
// StreamWriter writer = new StreamWriter(new FileStream("file.txt", FileMode.OpenOrCreate));
byte[] bytes = new byte[] { 0xff, 0xfe };
writer.BaseStream.Write(bytes, 0, bytes.Length);

If I recall correctly from your question. You want to write strings to a file and then write bytes to it?
This example will do that for you:
using (FileStream fsStream = new FileStream("Bytes.data", FileMode.Create))
using (BinaryWriter writer = new BinaryWriter(fsStream, Encoding.UTF8))
{
// Writing the strings.
writer.Write("The");
writer.Write(" strings");
writer.Write(" I");
writer.Write(" want");
writer.Write(".");
// Writing your bytes afterwards.
writer.Write(new byte[]
{
0xff,
0xfe
});
}
When opening the "Bytes.data" file with a hex editor you should see these bytes:

Here is one more way to look for a solution...
StringBuilder sb = new StringBuilder();
sb.Append("Hello!! ").Append(",");
sb.Append("My").Append(",");
sb.Append("name").Append(",");
sb.Append("is").Append(",");
sb.Append("Rajesh");
sb.AppendLine();
//use UTF8Encoding(true) if you want to use Byte Order Mark (BOM)
UTF8Encoding utf8withNoBOM = new UTF8Encoding(false);
byte[] bytearray;
bytearray = utf8withNoBOM.GetBytes(sb.ToString());
using (FileStream fileStream = new FileStream(System.Web.HttpContext.Current.Request.MapPath("~/" + "MyFileName.csv"), FileMode.Append, FileAccess.Write))
{
StreamWriter sw = new StreamWriter(fileStream, utf8withNoBOM);
//StreamWriter for writing bytestream array to file document
sw.BaseStream.Write(bytearray, 0, bytearray.Length);
sw.Flush();
sw.Close();
fileStream.Close();
}

If I understand correctly, you're trying to write some strings to a text file, but you want to add 2 bytes to this file.
Why won't you try using: File.WriteAllBytes ?
Convert your string to a Byte array using
byte[] byteArray = System.Text.Encoding.UTF8.GetBytes(str); // If your using UTF8
Create a new byte array from the original byteArray with the additional 2 bytes.
And write them to a file using:
File.WriteAllBytes("MyFile.dat", newByteArray)

There is a StreamWriter.Write(char) that will write a 16-bit value. You should be able to set your variable with the hex value like char val = '\xFFFE' and pass it to Write. You could also use FileStream where all the Write methods work off bytes, and it specifically has a WriteByte(byte) method. The MSDN documentation for it gives an example of outputting UTF8 text.

After saving the string simply write those bytes using for example using File.WriteAllBytes or a BinaryWriter:
Can a Byte[] Array be written to a file in C#?

StreamReader vs BinaryReader?

Both StreamReader and BinaryReader can be used to get data from binary file ( for example )
BinaryReader :
using (FileStream fs = File.Open(#"c:\1.bin",FileMode.Open))
{
byte[] data = new BinaryReader(fs).ReadBytes((int)fs.Length);
Encoding.getstring....
}
StreamReader :
using (FileStream fs = File.Open(#"c:\1.bin",FileMode.Open))
{
using (StreamReader sr = new StreamReader(fs,Encoding.UTF8))
{
var myString=sr.ReadToEnd();
}
}
What is the difference and when should I use which ?

Both StreamReader and BinaryReader can be used to get data from binary file
Well, StreamReader can be used to get text data from a binary representation of text.
BinaryReader can be used to get arbitrary binary data. If some of that binary data happens to be a representation of text, that's fine - but it doesn't have to be.
Bottom line:
If the entirety of your data is a straightforward binary encoding of text data, use StreamReader.
If you've fundamentally got binary data which may happen to have some portions in text, use BinaryReader
So for example, you wouldn't try to read a JPEG file with StreamReader.

how to read this text from file

how to read the text below?
‰€ˆ‡‰�#îõ‘þüŠ ꑯõù ‚†ƒ� -#�ª÷‘þü “‘
ª“îù )øþ¦ùý ¤ª—ùý î‘õ•þø—¤(#•¢þ¢�
ø¤÷¢ù ꑯõù îõ‘þü#^a—ú¤�ö^b•¦øû÷¢ð‘ö
¤�ù ¢�÷©^cˆˆƒ�#‚€� «.: õ¬ø¤Š
›¢øñ#…�…ˆí/Š…/
…€�…Š}TK{^aˆˆƒ�#†/„€€#}BF{#ª“îùû‘ý
î‘õ•þø—¤ý#ª“îùû‘ý î‘õ•þø—¤ý --
�¥õøöû‘#^c
I use this code but not display all characters
FileStream fs = new FileStream(open.FileName, FileMode.Open, FileAccess.Read);
System.Text.Encoding enc = System.Text.Encoding.UTF8 ;
byte[] data = new byte[fs.Length];
fs.Read(data, 0, data.Length);
string text = enc.GetString(data);
and show text :
†‰€ˆ‡‰Â�#îõâ� �˜Ã¾Ã¼Å
ꑯõù ‚†ƒ� -#�ª÷‘þü
“‘ ª“îù )øþ¦ùý
¤ª—ùý î‘õ•þø—¤(#�
�¢þ¢� ø¤÷¢ù ꑯõù
îõ‘þü#^a—ú¤�ö
^b•¦øû÷¢ð‘ö ¤�ù
¢Â�֩^cˆˆƒÂ�#‚₠¬Â� «.:
õ¬ø¤Š›¢øñ#…Â�…ˆí/Å
…/ …€Â�…Š}TK{^aˆˆƒÂ�#â€
/„€€#}BF{#ª“îùû ‘ý
î‘õ•þø—¤ý#�
�“îùû‘ý î‘õ
this is a TEXT DOS
and encoding this text is:
IBM037
IBM437
IBM500
ASMO-708
DOS-720
ibm737
ibm775
ibm850
ibm852
IBM855
ibm857
IBM00858
IBM860
ibm861
DOS-862
IBM863
IBM864
IBM865
cp866
ibm869
IBM870
windows-874
cp875
shift_jis
gb2312
ks_c_5601-1987
big5
IBM1026
IBM01047
IBM01140
IBM01141
IBM01142
IBM01143
IBM01144
IBM01145
IBM01146
IBM01147
IBM01148
IBM01149
utf-16
unicodeFFFE
windows-1250
windows-1251
Windows-1252
windows-1253
windows-1254
windows-1255
windows-1256
windows-1257
windows-1258
Johab
macintosh
x-mac-japanese
x-mac-chinesetrad
x-mac-korean
x-mac-arabic
x-mac-hebrew
x-mac-greek
x-mac-cyrillic
x-mac-chinesesimp
x-mac-romanian
x-mac-ukrainian
x-mac-thai
x-mac-ce
x-mac-icelandic
x-mac-turkish
x-mac-croatian
utf-32
utf-32BE
x-Chinese-CNS
x-cp20001
x-Chinese-Eten
x-cp20003
x-cp20004
x-cp20005
x-IA5
x-IA5-German
x-IA5-Swedish
x-IA5-Norwegian
us-ascii
x-cp20261
x-cp20269
IBM273
IBM277
IBM278
IBM280
IBM284
IBM285
IBM290
IBM297
IBM420
IBM423
IBM424
x-EBCDIC-KoreanExtended
IBM-Thai
koi8-r
IBM871
IBM880
IBM905
IBM00924
EUC-JP
x-cp20936
x-cp20949
cp1025
koi8-u
iso-8859-1
iso-8859-2
iso-8859-3
iso-8859-4
iso-8859-5
iso-8859-6
iso-8859-7
iso-8859-8
iso-8859-9
iso-8859-13
iso-8859-15
x-Europa
iso-8859-8-i
iso-2022-jp
csISO2022JP
iso-2022-jp
iso-2022-kr
x-cp50227
euc-jp
EUC-CN
euc-kr
hz-gb-2312
GB18030
x-iscii-de
x-iscii-be
x-iscii-ta
x-iscii-te
x-iscii-as
x-iscii-or
x-iscii-ka
x-iscii-ma
x-iscii-gu
x-iscii-pa
utf-7
utf-8

To read the file you need to know what encoding used in this file.
If you don't know, you can iterate through all encodings and see if find the one that works.
const string FileName = "FileName";
foreach (var encodingInfo in Encoding.GetEncodings())
{
try
{
var encoding = encodingInfo.GetEncoding();
var text = File.ReadAllText(FileName, encoding);
Console.WriteLine("{0} - {1}", encodingInfo.Name, text.Substring(0, 20));
// put break point and check if text is readable here
}
catch (Exception ex)
{
Console.WriteLine("Failed: {0}", encodingInfo.Name);
}
}
Disclaimer: assuming this is a text file, assuming the file isn't huge.

Well it looks like you're trying to open a .dat file, which is probably written with a byte format by the looks of it
Try the following code
File readThis = new File("file directory");
byte[] aByte = new byte[(int)readThis.length()];
FileInputStream Fis = new FileInputStream(readThis);
Fis.read(aByte);
System.out.println(Contents: "+aByte);
Fis.close();
Let me know how it goes :)