Base64ToString (String function): Difference between revisions

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equals signs are added and the encoded string might not be an exact multiple                 
equals signs are added and the encoded string might not be an exact multiple                 
of four bytes).                                                                               
of four bytes).                                                                               
*The inverse of Base64toString is [[Intrinsic StringToBase64 Function|StringToBase64]].    
*The inverse of Base64toString is [[StringToBase64 (String function)|StringToBase64]].
 
===Examples===                                                                               
===Examples===                                                                               
                                                                                              
                                                                                              

Revision as of 21:57, 21 October 2010

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.

Base64toString syntax

  %outStr = string:base64toString                                                                    

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