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How can I extract xml file encoding using streamreader?

I needed to get the encoding type from the top of the xml file
<?xml version=“1.0” encoding=“utf-8”?>
but only the encoding="utf-8" is needed
the "utf-8" only without the quotation mark, how can I achieve this using streamreader?

You need utf-8 or encoding="utf-8" ? this block returns utf-8 as a result. If you need encoding="utf-8", you need to change.
using (var sr = new StreamReader(#"yourXmlFilePath"))
{
var settings = new XmlReaderSettings { ConformanceLevel = ConformanceLevel.Fragment };
using (var xmlReader = XmlReader.Create(sr, settings))
{
if (!xmlReader.Read()) throw new Exception("No line");
var result = xmlReader.GetAttribute("encoding"); //returns utf-8
}
}

Since it's xml, I would recommend XmlTextReader that provides fast, non-cached, forward-only access to XML data and read just top of the xml file since declaration is there. See following method:
string FindXmlEncoding(string path)
{
XmlTextReader reader = new XmlTextReader(path);
reader.Read();
if (reader.NodeType == XmlNodeType.XmlDeclaration)
{
while (reader.MoveToNextAttribute())
{
if (reader.Name == "encoding")
return reader.Value;
}
}
return null;
}

how can I achieve this using StreamReader?
Something like this:
using (StreamReader sr = new StreamReader("XmlFile.xml"))
{
string line = sr.ReadLine();
int closeQuoteIndex = line.LastIndexOf("\"") - 1;
int openingQuoteIndex = line.LastIndexOf("\"", closeQuoteIndex);
string encoding = line.Substring(openingQuoteIndex + 1, closeQuoteIndex - openingQuoteIndex);
}

const string ENCODING_TAG = "encoding"; //You are searching for this. Lets make it constant.
string line = streamReader.ReadLine(); //Use your reader here
int start = line.IndexOf(ENCODING_TAG);
start = line.IndexOf('"', start)+1; //Start of the value
int end = line.IndexOf('"', start); //End of the value
string encoding = line.Substring(start, end-start);
NOTE: This approach expects the encoding to be in the first line of an existing declaration. Which it does not need to be.

Replacing Special Character with their codes

I am passing XML data to a server from a text Box, now issue is XML is giving issues with symbols like & < |. So i want to replace these symbols with their equivalent codes.
if i use string.replace function it will replace the characters recently replaced as well.
.Replace("&", "&")
.Replace("<", "<")
.Replace("|", "|")
.Replace("!", "!")
.Replace("#", "#")
As it go through complete string again and again.
So &<# will become "&#38;&#60;"
I also tried Dictionary method:
var replacements = new Dictionary<string, string>
{
{"&", "&"},
{"<", "<"},
{"|", "|"},
{"!", "!"},
{"#", "#"}
}
var output = replacements.Aggregate(input, (current, replacement) => current.Replace(replacement.Key, replacement.Value));
return output;
But same issue here as well. I also tried string builder method, but same repeating replacement issue. Any Advise?

You shouldn't be trying to escape characters manually. There are libraries and methods that are already built to do this such the SecurityElement.Escape(). It specifically escapes invalid XML characters into a known safe format that can be unescaped later.

I strongly advise using proper XML handling to build XML:
var id = 3;
var message = "&'<crazyMessage&&";
var xmlDoc = new XmlDocument();
using(var writer = xmlDoc.CreateNavigator().AppendChild())
{
writer.WriteStartElement("ROOT");
writer.WriteElementString("ID", id.ToString());
writer.WriteStartElement("INPUT");
writer.WriteElementString("ENGMSG", message);
writer.WriteEndElement(); // INPUT
writer.WriteEndElement(); // ROOT
}
var xmlString = xmlDoc.InnerXml;
Console.WriteLine(xmlString);
Ideone example
If you are using .NET 3.5 or higher, you can use Linq2Xml to build the XML, which is a bit cleaner:
var id = 3;
var message = "&'<crazyMessage&&";
var xml = new XElement("ROOT",
new XElement("ID", id),
new XElement("INPUT",
new XElement("ENGMSG", message)
)
);
var xmlString = xml.ToString();
Console.WriteLine(xmlString);

public static string Transform(string input, Dictionary<string, string> replacements)
{
string finalString = string.Empty;
for (int i = 0; i < input.Length; i++)
{
if (replacements.ContainsKey(input[i].ToString()))
{
finalString = finalString + replacements[input[i].ToString()];
}
else
{
finalString = finalString + input[i].ToString();
}
}
return finalString;
}

How can I read a Lync conversation file containing HTML?

I'm having trouble reading a local file, into a string, in c#.
Here's what I came up with till now:
string file = #"C:\script_test\{5461EC8C-89E6-40D1-8525-774340083829}.html";
using (StreamReader reader = new StreamReader(file))
{
string line = "";
while ((line = reader.ReadLine()) != null)
{
textBox1.Text += line.ToString();
}
}
And it's the only solution that seems to work.
I've tried some other suggested methods for reading a file, such as:
string file = #"C:\script_test\{5461EC8C-89E6-40D1-8525-774340083829}.html";
string html = File.ReadAllText(file).ToString();
textBox1.Text += html;
Yet it does not work as expected.
Here are the first few lines of the file i'm trying to read:
as you can see, it has some funky characters, honestly I don't know if that's the cause of this weird behavior.
But in the first case, the code seems to skip those lines, printing only "Document generated by Office Communicator..."

Your task would be easier if you could use an API or the SDK or even would have a description of the format you try to read. However the binary format looks not to be that complicated and with an hexviewer installed I got this far to get the html out of the example you provided.
To parse non-text files you fall-back to the BinaryReader and then use one of the Read methods to read the correct type from the bytestream. I used ReadByte and ReadInt32. Notice how in the description of the method is explained how many bytes are read. That becomes handy when you try to decipher your file.
private string ParseHist(string file)
{
using (var f = File.Open(file, FileMode.Open))
{
using (var br = new BinaryReader(f))
{
// read 4 bytes as an int
var first = br.ReadInt32();
// read integer / zero ended byte arrays as string
var lead = br.ReadInt32();
// until we have 4 zero bytes
while (lead != 0)
{
var user = ParseString(br);
Trace.Write(lead);
Trace.Write(":");
Trace.Write(user.Length);
Trace.Write(":");
Trace.WriteLine(user);
lead = br.ReadInt32();
// weird special case
if (lead == 2)
{
lead = br.ReadInt32();
}
}
// at the start of the html block
var htmllen = br.ReadInt32();
Trace.WriteLine(htmllen);
// parse the html
var html = ParseString(br);
Trace.Write(len);
Trace.Write(":");
Trace.Write(html.Length);
Trace.Write(":");
Trace.WriteLine(html);
// other structures follow, left unparsed
return html.ToString();
}
}
}
// a string seems to be ascii encoded and ends with a zero byte.
private static string ParseString(BinaryReader br)
{
var ch = br.ReadByte();
var sb = new StringBuilder();
while (ch != 0)
{
sb.Append((char)ch);
ch = br.ReadByte();
}
return sb.ToString();
}
You could use the simple parsing logic in a winform application as follows:
private void button1_Click(object sender, EventArgs e)
{
webBrowser1.DocumentText = ParseHist(#"5461EC8C-89E6-40D1-8525-774340083829-Copia.html");
}
Keep in mind that this is not bullet proof or the recommended way but it should get you started. For files that don't parse well you'll need to go back to the hexviewer and work-out what other byte structures are new or different from what you already had. That is not something I intend to help you with, that is left as an exercise for you to figure out.

I don't know if it's the right way to answer this, but here's what I've managed to do so far:
string file = #"C:\script_test\{1C0365BC-54C6-4D31-A1C1-586C4575F9EA}.hist";
string outText = "";
//Encoding iso = Encoding.GetEncoding("ISO-8859-1");
Encoding utf8 = Encoding.UTF8;
StreamReader reader = new StreamReader(file, utf8);
char[] text = reader.ReadToEnd().ToCharArray();
//skip first n chars
/*
for (int i = 250; i < text.Length; i++)
{
outText += text[i];
}
*/
for (int i = 0; i < text.Length; i++)
{
//skips non printable characters
if (!Char.IsControl(text[i]))
{
outText += text[i];
}
}
string source = "";
source = WebUtility.HtmlDecode(outText);
HtmlAgilityPack.HtmlDocument htmlDoc = new HtmlAgilityPack.HtmlDocument();
htmlDoc.LoadHtml(source);
string html = "<html><style>";
foreach (HtmlNode node in htmlDoc.DocumentNode.SelectNodes("//style"))
{
html += node.InnerHtml+ Environment.NewLine;
}
html += "</style><body>";
foreach (HtmlNode node in htmlDoc.DocumentNode.SelectNodes("//body"))
{
html += node.InnerHtml + Environment.NewLine;
}
html += "</body></html>";
richTextBox1.Text += html+Environment.NewLine;
webBrowser1.DocumentText = html;
The conversation displays correctly, both style and encoding.
So it's a start for me.
Thank you all for the support!
EDIT
Char.IsControl(char)
skips non printable characters :)

Saving an XML that has invalid characters

there are code snippets that strip the invalid characters inside a string before we save it as an XML ... but I have one more problem: Let's say my user wants to have a column name like "[MyColumnOne] ...so now I do not want to strip these "[","] well because these are the ones that user has defined and wants to see them so if I use some codes that are stripping the invalid characters they are also removing "[" and "[" but in this case I still need them to be saved... what can I do?

Never mind, I changed my RegEx format to use XML 1.1 instead of XML 1.0 and now it is working good :
string pattern = String.Empty;
//pattern = #"#x((10?|[2-F])FFF[EF]|FDD[0-9A-F]|7F|8[0-46-9A-F]9[0-9A-F])"; //XML 1.0
pattern = #"#x((10?|[2-F])FFF[EF]|FDD[0-9A-F]|[19][0-9A-F]|7F|8[0-46-9A-F]|0?[1-8BCEF])"; // XML 1.1
Regex regex = new Regex(pattern, RegexOptions.IgnoreCase);
if (regex.IsMatch(sString))
{
sString = regex.Replace(sString, String.Empty);
File.WriteAllText(sString, sString, Encoding.UTF8);
}
return sString;

This worked for me, and it was fast.
private object NormalizeString(object p) {
object result = p;
if (p is string || p is long) {
string s = string.Format("{0}", p);
string resultString = s.Trim();
if (string.IsNullOrWhiteSpace(resultString)) return "";
Regex rxInvalidChars = new Regex("[\r\n\t]+", RegexOptions.IgnoreCase);
if (rxInvalidChars.IsMatch(resultString)) {
resultString = rxInvalidChars.Replace(resultString, " ");
}
//string pattern = String.Empty;
//pattern = #"";
////pattern = #"#x((10?|[2-F])FFF[EF]|FDD[0-9A-F]|7F|8[0-46-9A-F]9[0-9A-F])"; //XML 1.0
////pattern = #"#x((10?|[2-F])FFF[EF]|FDD[0-9A-F]|[19][0-9A-F]|7F|8[0-46-9A-F]|0?[1-8BCEF])"; // XML 1.1
//Regex rxInvalidXMLChars = new Regex(pattern, RegexOptions.IgnoreCase);
//if (rxInvalidXMLChars.IsMatch(resultString)) {
// resultString = rxInvalidXMLChars.Replace(resultString, "");
//}
result = string.Join("", resultString.Where(c => c >= ' '));
}
return result;
}

C# Find if a word is in a document

I am looking for a way to check if the "foo" word is present in a text file using C#.
I may use a regular expression but I'm not sure that is going to work if the word is splitted in two lines. I got the same issue with a streamreader that enumerates over the lines.
Any comments ?

What's wrong with a simple search?
If the file is not large, and memory is not a problem, simply read the entire file into a string (ReadToEnd() method), and use string Contains()

Here ya go. So we look at the string as we read the file and we keep track of the first word last word combo and check to see if matches your pattern.
string pattern = "foo";
string input = null;
string lastword = string.Empty;
string firstword = string.Empty;
bool result = false;
FileStream FS = new FileStream("File name and path", FileMode.Open, FileAccess.Read, FileShare.Read);
StreamReader SR = new StreamReader(FS);
while ((input = SR.ReadLine()) != null)
{
firstword = input.Substring(0, input.IndexOf(" "));
if(lastword.Trim() != string.Empty) { firstword = lastword.Trim() + firstword.Trim(); }
Regex RegPattern = new Regex(pattern);
Match Match1 = RegPattern.Match(input);
string value1 = Match1.ToString();
if (pattern.Trim() == firstword.Trim() || value1 != string.Empty) { result = true; }
lastword = input.Trim().Substring(input.Trim().LastIndexOf(" "));
}

Here is a quick quick example using LINQ
static void Main(string[] args)
{
{ //LINQ version
bool hasFoo = "file.txt".AsLines()
.Any(l => l.Contains("foo"));
}
{ // No LINQ or Extension Methods needed
bool hasFoo = false;
foreach (var line in Tools.AsLines("file.txt"))
if (line.Contains("foo"))
{
hasFoo = true;
break;
}
}
}
}
public static class Tools
{
public static IEnumerable<string> AsLines(this string filename)
{
using (var reader = new StreamReader(filename))
while (!reader.EndOfStream)
{
var line = reader.ReadLine();
while (line.EndsWith("-") && !reader.EndOfStream)
line = line.Substring(0, line.Length - 1)
+ reader.ReadLine();
yield return line;
}
}
}

What about if the line contains football? Or fool? If you are going to go down the regular expression route you need to look for word boundaries.
Regex r = new Regex("\bfoo\b");
Also ensure you are taking into consideration case insensitivity if you need to.

You don't need regular expressions in a case this simple. Simply loop over the lines and check if it contains foo.
using (StreamReader sr = File.Open("filename", FileMode.Open, FileAccess.Read))
{
string line = null;
while (!sr.EndOfStream) {
line = sr.ReadLine();
if (line.Contains("foo"))
{
// foo was found in the file
}
}
}

You could construct a regex which allows for newlines to be placed between every character.
private static bool IsSubstring(string input, string substring)
{
string[] letters = new string[substring.Length];
for (int i = 0; i < substring.Length; i += 1)
{
letters[i] = substring[i].ToString();
}
string regex = #"\b" + string.Join(#"(\r?\n?)", letters) + #"\b";
return Regex.IsMatch(input, regex, RegexOptions.ExplicitCapture);
}