public string Format(string format, object arg, IFormatProvider formatProvider)
{
// This is the case we need to special case. We trust the IHtmlContent instance to do the
// right thing with encoding.
var htmlContent = arg as IHtmlContent;
if (htmlContent != null)
{
using (var writer = new StringWriter())
{
htmlContent.WriteTo(writer, _encoder);
return(writer.ToString());
}
}
// If we get here then 'arg' is not an IHtmlContent, and we want to handle it the way a normal
// string.Format would work, but then HTML encode the result.
//
// First check for an ICustomFormatter - if the IFormatProvider is a CultureInfo, then it's likely
// that ICustomFormatter will be null.
var customFormatter = (ICustomFormatter)_formatProvider.GetFormat(typeof(ICustomFormatter));
if (customFormatter != null)
{
var result = customFormatter.Format(format, arg, _formatProvider);
if (result != null)
{
return(_encoder.HtmlEncode(result));
}
}
// Next check if 'arg' is an IFormattable (DateTime is an example).
//
// An IFormattable will likely call back into the IFormatterProvider and ask for more information
// about how to format itself. This is the typical case when IFormatterProvider is a CultureInfo.
var formattable = arg as IFormattable;
if (formattable != null)
{
var result = formattable.ToString(format, _formatProvider);
if (result != null)
{
return(_encoder.HtmlEncode(result));
}
}
// If we get here then there's nothing really smart left to try.
if (arg != null)
{
var result = arg.ToString();
if (result != null)
{
return(_encoder.HtmlEncode(result));
}
}
return(string.Empty);
}
private static void WriteTo(TextWriter writer, IHtmlEncoder encoder, string value)
{
if (!string.IsNullOrEmpty(value))
{
encoder.HtmlEncode(value, writer);
}
}
private void AppendToOutputBuffer(object[] arguments, StringBuilder tokenBuffer, StringBuilder outputBuffer)
{
if (tokenBuffer != null && tokenBuffer.Length > 0)
{
outputBuffer.Append(_encoder.HtmlEncode(string.Format(tokenBuffer.ToString(), arguments)));
}
}
/// <inheritdoc />
public void WriteTo(TextWriter writer, IHtmlEncoder encoder)
{
if (writer == null)
{
throw new ArgumentNullException(nameof(writer));
}
if (encoder == null)
{
throw new ArgumentNullException(nameof(encoder));
}
foreach (var entry in Entries)
{
if (entry == null)
{
continue;
}
var entryAsString = entry as string;
if (entryAsString != null)
{
encoder.HtmlEncode(entryAsString, writer);
}
else
{
// Only string, IHtmlContent values can be added to the buffer.
((IHtmlContent)entry).WriteTo(writer, encoder);
}
}
}
private TimeSpan EncodeHtml(IHtmlEncoder encoder, string text, Stopwatch timer, int iterations)
{
timer.Restart();
for (int iteration = 0; iteration < iterations; iteration++)
{
Ignore(encoder.HtmlEncode(text));
}
return(timer.Elapsed);
}
/// <summary>
/// HTML-encodes a string and writes the result to the supplied output.
/// </summary>
/// <remarks>
/// The encoded value is also safe for inclusion inside an HTML attribute
/// as long as the attribute value is surrounded by single or double quotes.
/// </remarks>
public static void HtmlEncode(this IHtmlEncoder htmlEncoder, string value, TextWriter output)
{
if (htmlEncoder == null)
{
throw new ArgumentNullException(nameof(htmlEncoder));
}
if (!String.IsNullOrEmpty(value))
{
htmlEncoder.HtmlEncode(value, 0, value.Length, output);
}
}
/// <inheritdoc />
public void WriteTo(TextWriter writer, IHtmlEncoder encoder)
{
if (writer == null)
{
throw new ArgumentNullException(nameof(writer));
}
if (encoder == null)
{
throw new ArgumentNullException(nameof(encoder));
}
encoder.HtmlEncode(_input, writer);
}
/// <inheritdoc />
public void WriteTo(TextWriter writer, IHtmlEncoder encoder)
{
if (writer == null)
{
throw new ArgumentNullException(nameof(writer));
}
if (encoder == null)
{
throw new ArgumentNullException(nameof(encoder));
}
encoder.HtmlEncode(_input, writer);
}
private static TimeSpan EncodeHtmlToTextWriter(IHtmlEncoder encoder, string text, Stopwatch timer, int iterations)
{
var defaultEncoder = System.Text.Encodings.Web.HtmlEncoder.Default;
var stream = new MemoryStream(text.Length * 2 * defaultEncoder.MaxOutputCharactersPerInputCharacter);
var writer = new StreamWriter(stream);
timer.Restart();
for (int iteration = 0; iteration < iterations; iteration++)
{
encoder.HtmlEncode(text, writer);
}
writer.Flush();
writer.Dispose();
return(timer.Elapsed);
}
private void AppendAttributes(TextWriter writer, IHtmlEncoder encoder)
{
foreach (var attribute in Attributes)
{
var key = attribute.Key;
if (string.Equals(key, "id", StringComparison.OrdinalIgnoreCase) &&
string.IsNullOrEmpty(attribute.Value))
{
continue;
}
writer.Write(" ");
writer.Write(key);
writer.Write("=\"");
encoder.HtmlEncode(attribute.Value, writer);
writer.Write("\"");
}
}
protected object[] EncodeArguments(object[] arguments)
{
object[] encodedArguments = new object[arguments.Length];
for (var index = 0; index != arguments.Length; ++index)
{
var argument = arguments[index];
if (argument.GetType().GetTypeInfo().IsPrimitive ||
argument is HtmlString ||
argument is DateTime ||
argument is DateTimeOffset)
{
encodedArguments[index] = argument;
}
else
{
encodedArguments[index] = _encoder.HtmlEncode(argument.ToString());
}
}
return(encodedArguments);
}
private void AppendAttributes(TextWriter writer, IHtmlEncoder encoder)
{
// Perf: Avoid allocating enumerator for `_attributes` if possible
if (_attributes != null && _attributes.Count > 0)
{
foreach (var attribute in Attributes)
{
var key = attribute.Key;
if (string.Equals(key, "id", StringComparison.OrdinalIgnoreCase) &&
string.IsNullOrEmpty(attribute.Value))
{
continue;
}
writer.Write(" ");
writer.Write(key);
writer.Write("=\"");
encoder.HtmlEncode(attribute.Value, writer);
writer.Write("\"");
}
}
}
/// <inheritdoc />
public void WriteTo([NotNull] TextWriter writer, [NotNull] IHtmlEncoder encoder)
{
encoder.HtmlEncode(_input, writer);
}
/// <inheritdoc />
public string Encode(string value)
{
return(!string.IsNullOrEmpty(value) ? _htmlEncoder.HtmlEncode(value) : string.Empty);
}
public void WriteTo(TextWriter writer, IHtmlEncoder encoder)
{
encoder.HtmlEncode(Value, writer);
}
public void WriteTo(TextWriter writer, IHtmlEncoder encoder)
{
encoder.HtmlEncode(Value, writer);
}
private static string HtmlEncode(string body)
{
return(_htmlEncoder.HtmlEncode(body));
}
/// <inheritdoc />
public void WriteTo(TextWriter writer, IHtmlEncoder encoder)
{
if (writer == null)
{
throw new ArgumentNullException(nameof(writer));
}
if (encoder == null)
{
throw new ArgumentNullException(nameof(encoder));
}
foreach (var entry in Entries)
{
if (entry == null)
{
continue;
}
var entryAsString = entry as string;
if (entryAsString != null)
{
encoder.HtmlEncode(entryAsString, writer);
}
else
{
// Only string, IHtmlContent values can be added to the buffer.
((IHtmlContent)entry).WriteTo(writer, encoder);
}
}
}
