private void ParseValue()
{
int offset = 0;
try
{
// the disposition MUST be the first parameter in the string
_dispositionType = MailBnfHelper.ReadToken(_disposition, ref offset, null);
// disposition MUST not be empty
if (string.IsNullOrEmpty(_dispositionType))
{
throw new FormatException(Strings.MailHeaderFieldMalformedHeader);
}
// now we know that there are parameters so we must initialize or clear
// and parse
if (_parameters == null)
{
_parameters = new TrackingValidationObjectDictionary(s_validators);
}
else
{
_parameters.Clear();
}
while (MailBnfHelper.SkipCFWS(_disposition, ref offset))
{
// ensure that the separator charactor is present
if (_disposition[offset++] != ';')
{
throw new FormatException(string.Format(Strings.MailHeaderFieldInvalidCharacter, _disposition[offset - 1]));
}
// skip whitespace and see if there's anything left to parse or if we're done
if (!MailBnfHelper.SkipCFWS(_disposition, ref offset))
{
break;
}
string paramAttribute = MailBnfHelper.ReadParameterAttribute(_disposition, ref offset, null);
string paramValue;
// verify the next character after the parameter is correct
if (_disposition[offset++] != '=')
{
throw new FormatException(Strings.MailHeaderFieldMalformedHeader);
}
if (!MailBnfHelper.SkipCFWS(_disposition, ref offset))
{
// parameter was at end of string and has no value
// this is not valid
throw new FormatException(Strings.ContentDispositionInvalid);
}
paramValue = _disposition[offset] == '"' ?
MailBnfHelper.ReadQuotedString(_disposition, ref offset, null) :
MailBnfHelper.ReadToken(_disposition, ref offset, null);
// paramValue could potentially still be empty if it was a valid quoted string that
// contained no inner value. this is invalid
if (string.IsNullOrEmpty(paramAttribute) || string.IsNullOrEmpty(paramValue))
{
throw new FormatException(Strings.ContentDispositionInvalid);
}
// if validation is needed, the parameters dictionary will have a validator registered
// for the parameter that is being set so no additional formatting checks are needed here
Parameters.Add(paramAttribute, paramValue);
}
}
catch (FormatException exception)
{
// it's possible that something in MailBNFHelper could throw so ensure that we catch it and wrap it
// so that the exception has the correct text
throw new FormatException(Strings.ContentDispositionInvalid, exception);
}
_parameters.IsChanged = false;
}
// Helper methods.
private void ParseValue()
{
int offset = 0;
Exception exception = null;
try
{
_mediaType = MailBnfHelper.ReadToken(_type, ref offset, null);
if (_mediaType == null || _mediaType.Length == 0 || offset >= _type.Length || _type[offset++] != '/')
{
exception = new FormatException(Strings.ContentTypeInvalid);
}
if (exception == null)
{
_subType = MailBnfHelper.ReadToken(_type, ref offset, null);
if (_subType == null || _subType.Length == 0)
{
exception = new FormatException(Strings.ContentTypeInvalid);
}
}
if (exception == null)
{
while (MailBnfHelper.SkipCFWS(_type, ref offset))
{
if (_type[offset++] != ';')
{
exception = new FormatException(Strings.ContentTypeInvalid);
break;
}
if (!MailBnfHelper.SkipCFWS(_type, ref offset))
{
break;
}
string paramAttribute = MailBnfHelper.ReadParameterAttribute(_type, ref offset, null);
if (paramAttribute == null || paramAttribute.Length == 0)
{
exception = new FormatException(Strings.ContentTypeInvalid);
break;
}
string paramValue;
if (offset >= _type.Length || _type[offset++] != '=')
{
exception = new FormatException(Strings.ContentTypeInvalid);
break;
}
if (!MailBnfHelper.SkipCFWS(_type, ref offset))
{
exception = new FormatException(Strings.ContentTypeInvalid);
break;
}
paramValue = _type[offset] == '"' ?
MailBnfHelper.ReadQuotedString(_type, ref offset, null) :
MailBnfHelper.ReadToken(_type, ref offset, null);
if (paramValue == null)
{
exception = new FormatException(Strings.ContentTypeInvalid);
break;
}
_parameters.Add(paramAttribute, paramValue);
}
}
_parameters.IsChanged = false;
}
catch (FormatException)
{
throw new FormatException(Strings.ContentTypeInvalid);
}
if (exception != null)
{
throw new FormatException(Strings.ContentTypeInvalid);
}
}