Special characters in Web Development

URLSpecial characters in

URLThe special characters inURLAnd must be encoded. The encoding format is:%Character-addedASCIIA percent sign.%, Followed by the corresponding charactersASCII(16In hexadecimal notation.

 

Character	Name	16Hexadecimal value
+	URLIn+Space	% 2B
Space	URLSpace in can be used+ID or code	% 20
/	Split directories and subdirectories	% 2f
?	Separate the actualURLAnd Characters	% 3f
%	Special characters	% 25
#	Indicates bookmarks,URLTransmission Parameters are automatically truncated.#Subsequent content	% 23
&	URLParameter Separator in	% 26
=	UELParameter value specified in	% 3d

Example: to pass a string"This % is # Te = sT & o k? + /"As a parameterTPassTe. asp, ThenURLYes:
Te. asp? T = This % 25is % 23te % 3dst % 26o % 20 K % 3f % 2B % 2fOr
Te. asp? T = This % 25is % 23te % 3dst % 26o + K % 3f % 2B % 2f(Space can be used% 20Or+)

JavaMediumURLEncoding and decoding Functions:
Java.net. urlencoder. encode (string S)AndJava.net. urldecoder. Decode (string S );
InJavascriptMediumURLThe encoding and decoding functions areEscape (string S)AndUnescape (string S );

 

 

HtmlEscape characters in

Character	Escape characters	Description
&	& Amp;	And
<	& Lt;	Yu no.
>	& Gt;	Yu no.
"	& Quot;	Double quotation marks
'	& Amp; #39;	Single quotes
Space	& Nbsp;	Space
?	& Copy;	Copyright token
?	& Reg;	Register character

 

The former is the character escape sequence, and the latter is the numerical escape sequence. Convert a number to a characterASCIICode value. For example& Lt; font & gt;Displayed,<Font>Is considered as a link sign.

Note:

A.There cannot be spaces between characters in the escape sequence;

B.The escape sequence must start";"End;

C.Separate&It is not considered as the start of escape;

D.Case sensitive.

Another character that needs to be escaped is the quotation mark, and its turn-to-order Column"""Or"""

HtmlThe character set used isISO & 859 Larin-1Character Set, which contains many characters that cannot be entered on the standard keyboard. Only escape sequences can be used for these special characters.

 

XMLSpecial characters in

Character	Escape characters	Description
&	& Amp;	And
<	& Lt;	Yu no.
>	& Gt;	Yu no.
"	& Quot;	Double quotation marks
'	& Apos;	Single quotes

 

InvalidXMLCharacters must be escaped.XMLSimilar"<"Character,The parser will have an error, because the parser will think this is the beginning of a new element. So it should not be written as belowCode:

<Message> If salary <1000 then </message>

To avoid this"<"Convert to entity, as shown below:

<Message> If salary <1000 then </message>

 

 

JavascriptEscape characters in

Escape Sequence	Character
\ B	Return
\ F	Take the form of paper
\ N	Line feed
\ R	Enter
\ T	Horizontal hop
\"	Double quotation marks
\'	Single quotes
\\	Backslash

 

VaR TXT = "we are the so-called" Vikings "from the north ."

Document. Write (txt)

InJavascriptThe string starts and ends with double quotation marks or single quotation marks. This means that the above string will be chopped: We are the so-called

To solve this problem, you mustVikingAdd a backslash before and after double quotation marks(\)In this way, every double quotation mark is converted into a string text:

VaR TXT = "we are the so-called \" Vikings \ "from the north ."

Document. Write (txt)

NowJavasscriptThe string can be correctly displayed:We are the so-called"Vikings"From the north.

 

Here is another example:

Document. Write ("You \ & me are singing !")

The above example will generate the following output:

You & me are singing!

 

CookieSpecial characters in

version 0: by Netscape developed by the Company, it is also supported by almost all browsers . java to maintain compatibility , currently only versions are supported. 0, Cookie content cannot contain spaces, square brackets, Parentheses, equal to signs ( = ), comma, double quotation mark, slash, question mark, @ symbol, colon, semicolon.

version 1: according to RFC 2109 (http://www.ietf.org/rfc/rfc2109.txt) . many restrictions are relaxed . restrictions listed above . but to maintain compatibility , avoid using these special characters.