public InternalLocaleBuilder SetExtension(char singleton, string value)
{
// validate key
bool isBcpPrivateuse = LanguageTag.IsPrivateusePrefixChar(singleton);
if (!isBcpPrivateuse && !LanguageTag.IsExtensionSingletonChar(singleton))
{
throw new FormatException("Ill-formed extension key: " + singleton);
}
bool remove = (value == null || value.Length == 0);
CaseInsensitiveChar key = new CaseInsensitiveChar(singleton);
if (remove)
{
if (UnicodeLocaleExtension.IsSingletonChar(key.Value))
{
// clear entire Unicode locale extension
if (_uattributes != null)
{
_uattributes.Clear();
}
if (_ukeywords != null)
{
_ukeywords.Clear();
}
}
else
{
if (_extensions != null && _extensions.ContainsKey(key))
{
_extensions.Remove(key);
}
}
}
else
{
// validate value
string val = value.Replace(BaseLocale.Separator, LanguageTag.Separator);
StringTokenEnumerator itr = new StringTokenEnumerator(val, LanguageTag.Separator);
while (itr.MoveNext())
{
string s = itr.Current;
bool validSubtag;
if (isBcpPrivateuse)
{
validSubtag = LanguageTag.IsPrivateuseSubtag(s);
}
else
{
validSubtag = LanguageTag.IsExtensionSubtag(s);
}
if (!validSubtag)
{
throw new FormatException("Ill-formed extension value: " + s /*, itr.CurrentStart*/);
}
}
if (UnicodeLocaleExtension.IsSingletonChar(key.Value))
{
SetUnicodeLocaleExtension(val);
}
else
{
if (_extensions == null)
{
_extensions = new Dictionary <CaseInsensitiveChar, string>(4);
}
_extensions[key] = val;
}
}
return(this);
}
public static bool IsValidKey(char c)
{
return(LanguageTag.IsExtensionSingletonChar(c) || LanguageTag.IsPrivateusePrefixChar(c));
}