How to pass special characters based on javascript _ javascript skills

In JavaScript, a backslash is used to add special characters to a text string. The following article describes how to pass special characters in javascript, if you are interested in passing special characters in JavaScript, let's take a look at it. Before you get on the right track, we will introduce you to special JavaScript characters.

You can use a backslash in JavaScript to add special characters to a text string.

Insert special characters

A backslash is used to insert ellipsis, line breaks, quotation marks, and other special characters into a text string.

See the following JavaScript code:

var txt="We are the so-called "Vikings" from the north."document.write(txt)

In JavaScript, strings start or end with single or double quotation marks. This means that the above string will be truncated to: We are the so-called.
To solve this problem, you must add a backslash (\) before the quotation marks in "Viking (\). In this way, each double quotation mark can be converted to a literal string.

var txt="We are the so-called \"Vikings\" from the north."document.write(txt)

Now JavaScript can output the correct text string: We are the so-called "Vikings" from the north.

This is another example:

document.write ("You \& me are singing!") 

The preceding example generates the following output:

You & me are singing!

The following table lists other special characters that can be added to a text string using a backslash:

Code	Output
\'	Single quotes
\"	Double quotation marks
\&	And number
\\	Backslash
\ N	Line Break
\ R	Carriage Return
\ T	Tab
\ B	Escape Character
\ F	Page feed

Background:

When I was doing a task today, when I passed a long string of characters using jquery ajax, the verification in the background was always unsuccessful. When I struggled (the string was randomly generated and specialized ). after checking the morning, it turns out that there is a + sign in the source string that I generated. When passing the + sign in js, it will be understood as the connection character land. When it arrives at the background, it will automatically change the + sign to a space, therefore, the background strings are different from those generated at the foreground.

Cause:

Special characters are automatically parsed after js, such as the connector +, space, and variable connector. When the Server accepts data, the data in the future is not displayed.

Solution:

1. Place the characters in form and submit the form to the server using js.
2. Replace special characters with hexadecimal characters. Some special characters correspond to hexadecimal characters:

+	Space	/	?	%	&	=	#
% 2b	% 20	% 2f	% 3f	% 25	% 26	& 3d	% 23

Str = str. replace (/\ +/g, % 2b); replace the "+" with the hexadecimal notation.

3. Use the encodeuricomponent () function.

This method does not encode ascii letters and numbers, and does not encode these ascii punctuation marks :-_.! ~ *'().
Other characters (such :;/? : @ & =+ $, # The punctuation marks used to separate uri components) are all replaced by one or more hexadecimal sequence.

JQuery ajax Special Character Parameters

A problem encountered during ajax login. When the input parameter contains special characters, such as "$. The parameter is transmitted incorrectly.

$.ajax({  url: '/user/login.ydd',  type:'post',  data:'name=abce&password=abcd&pwd',  success: function(data){  }})

I want to input a user with the username abc and password abcd & pwd to log on. However, the parameter obtained in the background is passed as a parameter by password = abcd. & in this special example, pwd is separated and parsed as another parameter.

Solution: in this case, ajax needs another method to pass parameters.

$.ajax({  url: '/user/login.ydd',  type:'post',  data:{'name':'abce','password':'abcd&pwd'},  success: function(data){   }})