public static String ToString(InputStream stream, String encoding)
{
StreamReader sr = new StreamReader(stream);
return sr.ReadToEnd();
}
public static void CloseQuietly(InputStream stream)
{
stream.Close();
}
/// <summary>
/// <p>Sniffs encoding settings from the specified XML content and/or the corresponding HTTP headers using
/// a custom algorithm.</p>
/// <p>Note that if an encoding is found but it is not supported on the current platform, this method returns
/// <tt>null</tt>, as if no encoding had been found.</p>
/// </summary>
/// <param name="headers">the HTTP response headers sent back with the XML content to be sniffed</param>
/// <param name="content">the XML content to be sniffed</param>
/// <returns>the encoding sniffed from the specified XML content and/or the corresponding HTTP headers, or <tt>null</tt> if the encoding could not be determined</returns>
public static String SniffXmlEncoding(List<NameValuePair> headers, InputStream content)
{
String encoding = SniffEncodingFromHttpHeaders(headers);
if (encoding != null || content == null) {
return encoding;
}
byte[] bytes = Read(content, 3);
encoding = SniffEncodingFromUnicodeBom(bytes);
if (encoding != null) {
return encoding;
}
bytes = ReadAndPrepend(content, SIZE_OF_XML_CONTENT_SNIFFED, bytes);
encoding = SniffEncodingFromXmlDeclaration(bytes);
return encoding;
}
/// <summary>
/// <p>Sniffs encoding settings from the specified content of unknown type by looking for <tt>Content-Type</tt>
/// information in the HTTP headers and <a href="http://en.wikipedia.org/wiki/Byte_Order_Mark">Byte Order Mark</a>
/// information in the content.</p>
///
/// <p>Note that if an encoding is found but it is not supported on the current platform, this method returns
/// <tt>null</tt>, as if no encoding had been found.</p>
/// </summary>
/// <param name="headers">the HTTP response headers sent back with the content to be sniffed</param>
/// <param name="content">the content to be sniffed</param>
/// <returns>the encoding sniffed from the specified content and/or the corresponding HTTP headers, or <tt>null</tt> if the encoding could not be determined</returns>
public static String SniffUnknownContentTypeEncoding(List<NameValuePair> headers, InputStream content)
{
String encoding = SniffEncodingFromHttpHeaders(headers);
if (encoding != null || content == null) {
return encoding;
}
byte[] bytes = Read(content, 3);
encoding = SniffEncodingFromUnicodeBom(bytes);
return encoding;
}
/// <summary>
/// <p>If the specified content is HTML content, this method sniffs encoding settings
/// from the specified HTML content and/or the corresponding HTTP headers based on the
/// <a href="http://www.whatwg.org/specs/web-apps/current-work/multipage/parsing.html#determining-the-character-encoding">HTML5
/// encoding sniffing algorithm</a>.</p>
///
/// <p>If the specified content is XML content, this method sniffs encoding settings
/// from the specified XML content and/or the corresponding HTTP headers using a custom algorithm.</p>
///
/// <p>Otherwise, this method sniffs encoding settings from the specified content of unknown type by looking for
/// <tt>Content-Type</tt> information in the HTTP headers and
/// <a href="http://en.wikipedia.org/wiki/Byte_Order_Mark">Byte Order Mark</a> information in the content.</p>
///
/// <p>Note that if an encoding is found but it is not supported on the current platform, this method returns
/// <tt>null</tt>, as if no encoding had been found.</p>
/// </summary>
/// <param name="headers">the HTTP response headers sent back with the content to be sniffed</param>
/// <param name="content">the content to be sniffed</param>
/// <returns>the encoding sniffed from the specified content and/or the corresponding HTTP headers, or <tt>null</tt> if the encoding could not be determined</returns>
public static String SniffEncoding(List<NameValuePair> headers, InputStream content)
{
if (IsHtml(headers)) {
return SniffHtmlEncoding(headers, content);
}
else if (IsXml(headers)) {
return SniffXmlEncoding(headers, content);
}
else {
return SniffUnknownContentTypeEncoding(headers, content);
}
}
/// <summary>
/// Attempts to read <tt>size</tt> bytes from the specified input stream and then prepends the specified prefix to
/// the bytes read, returning the resultant byte array. Note that this method is not guaranteed to be able to read
/// <tt>size</tt> bytes; however, the returned byte array will always be the exact length of the number of bytes
/// read plus the length of the prefix array.
/// @throws IOException if an IO error occurs
/// </summary>
/// <param name="content">the input stream to read from</param>
/// <param name="size">the number of bytes to try to read</param>
/// <param name="prefix">the byte array to prepend to the bytes read from the specified input stream</param>
/// <returns>the bytes read from the specified input stream, prefixed by the specified prefix</returns>
static byte[] ReadAndPrepend(InputStream content, int size, byte[] prefix)
{
byte[] bytes = Read(content, size);
byte[] joined = new byte[prefix.Length + bytes.Length];
Array.Copy(prefix, 0, joined, 0, prefix.Length);
Array.Copy(bytes, 0, joined, prefix.Length, bytes.Length);
return joined;
}
/// <summary>
/// Attempts to read <tt>size</tt> bytes from the specified input stream. Note that this method is not guaranteed
/// to be able to read <tt>size</tt> bytes; however, the returned byte array will always be the exact length of the
/// number of bytes read.
/// @throws IOException if an IO error occurs
/// </summary>
/// <param name="content">the input stream to read from</param>
/// <param name="size">size the number of bytes to try to read</param>
/// <returns>the bytes read from the specified input stream</returns>
static byte[] Read(InputStream content, int size)
{
byte[] bytes = new byte[size];
int count = content.Read(bytes, 0, size);
if (count == -1) {
bytes = new byte[0];
}
else if (count < size) {
byte[] smaller = new byte[count];
Array.Copy(bytes, 0, smaller, 0, count);
bytes = smaller;
}
return bytes;
}
public InputStreamReader(InputStream stream):
base(stream)
{
}
public InputStreamReader(InputStream stream, Encoding encoding) :
base(stream, encoding)
{
}
