Base64ToString (String function)

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Convert a base 64 string to Ebcdic (String class)


This intrinsic function returns the unencoded value of a base-64 encoded string.

Base64toString is available as of version 7.2 of the Sirius Mods.

Syntax

%outString = string:Base64ToString Throws InvalidBase64Data

Syntax terms

%outStr A string variable to receive the unencoded value of the method object string.
string A Base64-encoded string value.

Exceptions

This intrinsic function can throw the following exceptions:

InvalidBase64data
If the method object string does not contain a properly encoded base64 value. The exception object indicates the position of the first invalid character in the method object string.

Usage notes

  • Base-64 encoding is useful for encoding strings that might contain

binary or other characters that could cause problems in certain contexts. For example, binary characters can be problematic when sent in e-mail.

Base-64 encoding is an alternative to hexadecimal encoding. Hexadecimal encoding has the advantage that it's simpler, but it has the disadvantage that it requires two bytes for every encoded byte. Base-64 encoding, because it uses more characters (64, as the name would suggest), only requires four bytes for every three encoded bytes.

  • A complete explanation of base-64 encoding can be easily found on the

internet or in many software textbooks.

  • The Base64toString function accepts both the standard base64 encoding

(where the encoded string is padded out to an even multiple of four bytes by adding trailing equals signs) and a non-standard encoding (where no trailing equals signs are added and the encoded string might not be an exact multiple of four bytes).

Examples

The following statement displays 'Sleeping Bear':

   printText {'4pOFhZeJlYdAwoWBmQ==':base64toString}

See also

List of intrinsic String methods