Url Encoding; Reserved Characters; Unsafe Characters - Extron electronics IPL T SF24 Series User Manual

Communication and Control, cont'd
Figure 4-31b — Browser view

URL encoding

URL encoding is the method of using ASCII hexadecimal
characters to display specific characters in a URL. URL
encoding is used for several reasons. On some operating
systems, certain characters are unsafe or not available, and
others are reserved by the HTML or URL specification. URL
encoding is used to insure compatibility and functionality with
most Internet browsers. As a general rule, use the hexadecimal
encoding method shown below when these characters appear in
your URLs.
The following types of characters do not require encoding in a
URL:
alphanumerics
special characters

reserved characters

IPL T SF24 and IPL T SFI244 • Communication and Control
4-38
0-9 a-z A-Z
$ _ _ . + ! * ( ) ,
; / ? : @ = &
When used for their reserved purposes, these
characters do not require encoding within a URL.
Reserved characters
Reserved characters should not be encoded when they appear
in their conventional meaning in a URL. For example, do not
encode the slash (/) when using it as part of the URL syntax.
Only encode unsafe characters (defined below) in your URLs.
The following table lists reserved characters.
Characters
$ Dollar
& Ampersand
+ Plus
, Comma
/ Forward Slash / Virgule
: Colon
; Semi-colon
= Equal
? Question Mark
@ "At" Symbol

Unsafe characters

URLs use some characters for "special use" in defining their
syntax and these characters should be encoded. For various
reasons, these characters present the possibility of being
misunderstood within a URL.
The following table lists unsafe characters.
Characters
Space
" " Quotation Marks
< "Less Than" Symbol
> "Greater Than" Symbol
Pound
#
% Percent
Miscellaneous Characters
{ Left Curly Brace
} Right Curly Brace
| Vertical Bar / Pipe
\ Backslash
^ Caret
~ Tilde
[ Left Square Bracket
] Right Square Bracket
` Grave Accent
IPL T SF24 and IPL T SFI244 • Communication and Control
Hex Dec
24 36
26 38
2B 43
2C 44
2F 47
3A 58
3B 59
3D 61
3F 63
40 64
Hex Dec
20 32
22 34
3C 60
3E 62
23 35
25 37
7B 123
7D 125
7C 124
5C 92
5E 94
7E 126
5B 91
5D 93
60 96
4-39