/// <summary>
/// Handles the special SPARQL escapes that can occur in a local name
/// </summary>
/// <remarks>
/// Unlike <see cref="BaseTokeniser.HandleEscapes()">HandleEscapes()</see> this only unescapes unicode escapes, other escapes are simply validated and passed through for later unescaping
/// </remarks>
protected void HandleSparqlLocalNameEscapes()
{
//Grab the first character which must be a \ or %
char next = this.SkipCharacter();
//Stuff for Unicode/Hex escapes
StringBuilder localOutput;
if (next == '\\')
{
//Backslash based escape
next = this.Peek();
switch (next)
{
case '_':
case '-':
case '.':
case '|':
case '$':
case '&':
case '\'':
case '(':
case ')':
case '*':
case '+':
case ',':
case ';':
case '=':
case ':':
case '/':
case '?':
case '#':
case '@':
case '%':
//Escapable Characters
this._output.Append('\\');
this.ConsumeCharacter();
return;
case 'u':
//Need to consume the u first
localOutput = new StringBuilder();
this.SkipCharacter();
next = this.Peek();
//Try to get Four Hex Digits
while (localOutput.Length < 4 && this.IsHexDigit(next))
{
localOutput.Append(next);
this.SkipCharacter();
next = this.Peek();
}
//Did we get four Hex Digits
if (localOutput.Length != 4)
{
throw Error("Unexpected Character (Code " + (int)next + "): " + next + " encountered while trying to parse Unicode Escape from Content:\n" + this._output.ToString() + "\nThe \\u Escape must be followed by four Hex Digits");
}
else if (localOutput.ToString().Equals("0000"))
{
//Ignore the null escape
}
else
{
this._output.Append(UnicodeSpecsHelper.ConvertToChar(localOutput.ToString()));
}
return;
case 'U':
//Need to consume the U first
localOutput = new StringBuilder();
this.SkipCharacter();
next = this.Peek();
//Try to get Eight Hex Digits
while (localOutput.Length < 8 && this.IsHexDigit(next))
{
localOutput.Append(next);
this.SkipCharacter();
next = this.Peek();
}
//Did we get eight Hex Digits
if (localOutput.Length != 8)
{
throw Error("Unexpected Character (Code " + (int)next + "): " + next + " encountered while trying to parse Unicode Escape from Content:\n" + this._output.ToString() + "\nThe \\U Escape must be followed by eight Hex Digits");
}
else if (localOutput.ToString().Equals("00000000"))
{
//Ignore the null escape
}
else
{
this._output.Append(UnicodeSpecsHelper.ConvertToChar(localOutput.ToString()));
}
return;
default:
throw Error("Unexpected Backslash Character encountered in a Local Name, the Backslash Character can only be used for Unicode escapes (\\u and \\U) and a limited set of special characters (_-.|&'()*+,;=/?#@%) in Local Names");
}
}
else if (next == '%')
{
localOutput = new StringBuilder();
localOutput.Append(next);
next = this.Peek();
while (localOutput.Length < 3 && this.IsHexDigit(next))
{
localOutput.Append(next);
this.SkipCharacter();
next = this.Peek();
}
//Did we get % followed by two hex digits
if (localOutput.Length != 3)
{
throw Error("Encountered a % character in a Local Name but the required two hex digits were not present after it, please use \\% if you wish to represent the percent character");
}
#if !SILVERLIGHT
else if (!Uri.IsHexEncoding(localOutput.ToString(), 0))
#else
else if (SilverlightExtensions.IsHexEncoding(localOutput.ToString(), 0))
#endif
{
throw Error("Invalid % encoded character encountered");
}
else
{
this._output.Append(localOutput.ToString());
}
}
else
{
throw Error("HandleSparqlLocalNameEscapes() was called but the next character is not a % or \\ as expected");
}
}
/// <summary>
/// Handles the complex escapes that can occur in a local name
/// </summary>
/// <remarks>
/// Unlike <see cref="BaseTokeniser.HandleEscapes(TokeniserEscapeMode)">HandleEscapes()</see> this only unescapes unicode escapes, other escapes are simply validated and passed through for later unescaping
/// </remarks>
protected void HandleComplexLocalNameEscapes()
{
//Grab the first character which must be a \ or %
char next = this.SkipCharacter();
//Stuff for Unicode/Hex escapes
if (next == '\\')
{
//Backslash based escape
next = this.Peek();
switch (next)
{
case '_':
case '~':
case '-':
case '.':
case '!':
case '$':
case '&':
case '\'':
case '(':
case ')':
case '*':
case '+':
case ',':
case ';':
case '=':
case '/':
case '?':
case '#':
case '@':
case '%':
//Escapable Characters
this._output.Append('\\');
this.ConsumeCharacter();
return;
case 'u':
case 'U':
throw Error("Illegal unicode escape (\\u or \\U) in local name portion of a prefixed name");
default:
throw Error("Unexpected Backslash Character encountered in a Local Name, the Backslash Character can only be used for Unicode escapes (\\u and \\U) and a limited set of special characters (_~-.!$&'()*+,;=/?#@%) in Local Names");
}
}
if (next != '%')
{
throw Error("HandleComplexLocalNameEscapes() was called but the next character is not a % or \\ as expected");
}
StringBuilder localOutput = new StringBuilder();
localOutput.Append(next);
next = this.Peek();
while (localOutput.Length < 3 && this.IsHexDigit(next))
{
localOutput.Append(next);
this.SkipCharacter();
next = this.Peek();
}
//Did we get % followed by two hex digits
if (localOutput.Length != 3)
{
throw Error("Encountered a % character in a Local Name but the required two hex digits were not present after it, please use \\% if you wish to represent the percent character itself");
}
#if !SILVERLIGHT
if (!Uri.IsHexEncoding(localOutput.ToString(), 0))
#else
if (SilverlightExtensions.IsHexEncoding(localOutput.ToString(), 0))
#endif
{
throw Error("Invalid % encoded character encountered");
}
this._output.Append(localOutput.ToString());
}
