What is the CodePage for DBCS so I can encode an xml string and show it in a asp.net text box?

Question

What is the CodePage for DBCS so I can encode an xml string and show it in a asp.net text box? I don't think I should have to convert the characters myself when Server.HTMLEncode will work if the string is DBCS.

To clarify: the binary represenation of the xml string(Base64) is stored in the database in a column of nvarchar(max) datatype.

Also if I remember correctly the web.config needs to be changed to show unicode I think I can't remember anymore it's been awhile.

Is this a limitation of the ASP.Net TextBox?

Any help would be greatly appreciated.

Thanks!