The DecodedText property is used to specify the decoded
value of a string, or return the decoded value of a previously
encoded string. If the property is set, the current plain (decoded)
text is changed to that value and reading the EncodedText
property will return the encoded string for this value. If the
property is read, it will return the decoded value of the
EncodedText property.
The control will use the value of the Encoding property to
determine how the text should be decoded. Note that only base64 and
quoted-printable encoding is supported when decoding a string using
this property. To decode the contents of a file, it's recommended
that you use the DecodeFile method.
The CodePage property affects how the
DecodedText and EncodedText property handles
encoding. By default it will use the UTF-8 code page to ensure that
non-ASCII characters are encoded correctly regardless of the current
locale. Using the current active code page can introduce errors in the
encoding if the string is decoded on a system using a different code
page.