If your textfile is an unstructured text (a letter or a novel) it doesn't make sense to convert it to xml.
If it is structured in some way, like a CSV-file, you might do some string-manupilations to get the pieces to put in different nodes. You could glue them together appending strings:
xmlstring = "<root><name>" + FirstPart + "</name><name>" + SecondPart + "</name></root>"
With a bit of luck, you can even use a replace-function (replace ";" with "</field><field>", replace newline with "</field></record><record><field>" or something like that.
But anyway, I'd advise to use (for example) MSXML.DOMDocument. Check the help that goes with it for instructions: it isn't difficult, and much safer then appending the strings yourself (one typo and your xml is invalid).