Table to XML (Visa Versa)

This question kinda goes with my other question: JPG to Base64

I need function which creates a XML file from a database table depending on first character of text of a particular field (FieldName) return true is successful and false if it failed, passing a errorcode

Function ExportToXML(Table: TTable; FieldName: String; C: CHar; FileNanme: String; var ErrorCode: Integer): Boolean
begin
 //
end;

I need function which loads the XML file to a database table and inserts each record if the record doesn' already exists (using fieldName) to searchon

Function ImportFromXML(Table: TTable; FieldName: String; FileName: String): Boolean
begin
 //
end;


Show an example using the following field types

Integer
Float
String
Date
Time
DateTime
Memo
Graphic  (only JPGs used)



memo and image (jpg) field data should be encoded in the XML file when exporting  and decoded back when importing

Im willing to use an unit or component (as long as they are free and are free to use in commercial apps)