Creating multiline strings in JavaScript (JS中字符串换行问题)

Q

I have the following code in Ruby. I want to convert this code into JavaScript. what’s the equivalent code in JS?

text = <<"HERE"
This
Is
A
Multiline
String
HERE

A-1

ECMAScript 6 (ES6) introduces a new type of literal, namely template literals. They have many features, variable interpolation among others, but most importantly for this question, they can be multiline.

ECMAScript 6(ES6)引入了一种新型的文字,即模板文字。它们具有许多功能,其中包括变量插值,但对于这个问题最重要的是,它们可以是多行的。

A template literal is delimited by backticks:

模板文字由反引号分隔:

var html = `
  <div>
    <span>Some HTML here</span>
  </div>
`;

(Note: I’m not advocating to use HTML in strings)

(注意:我不主张在字符串中使用HTML)

A-2

As the first answer mentions, with ES6/Babel, you can now create multi-line strings simply by using backticks:

如第一个答案所述,使用ES6 / Babel,您现在只需使用反引号即可创建多行字符串:

const htmlString = `Say hello to 
multi-line
strings!`;

Interpolating variables is a popular new feature that comes with back-tick delimited strings:

插值变量是流行的新功能,带有反引号分隔的字符串:

const htmlString = `${
      
      user.name} liked your post about strings`;

This just transpiles down to concatenation:

这只是转换为串联:

user.name + ' liked your post about strings'

Original ES5 answer:

ES5原始答案:

Google’s JavaScript style guide recommends to use string concatenation instead of escaping newlines:

Google的JavaScript样式指南建议使用字符串串联而不是换行符:

Do not do this:

不要这样做:

var myString = 'A rather long string of English text, an error message \
                actually that just keeps going and going -- an error \
                message to make the Energizer bunny blush (right through \
                those Schwarzenegger shades)! Where was I? Oh yes, \
                you\'ve got an error and all the extraneous whitespace is \
                just gravy.  Have a nice day.';

The whitespace at the beginning of each line can’t be safely stripped at compile time; whitespace after the slash will result in tricky errors; and while most script engines support this, it is not part of ECMAScript.

在编译时不能安全地剥离每行开头的空白;斜杠后的空格将导致棘手的错误;尽管大多数脚本引擎都支持此功能,但它不是ECMAScript的一部分。

Use string concatenation instead:

请使用字符串串联:

var myString = 'A rather long string of English text, an error message ' +
               'actually that just keeps going and going -- an error ' +
               'message to make the Energizer bunny blush (right through ' +
               'those Schwarzenegger shades)! Where was I? Oh yes, ' +
               'you\'ve got an error and all the extraneous whitespace is ' +
               'just gravy.  Have a nice day.';

A-3

the pattern text = <<"HERE" This Is A Multiline String HERE is not available in js (I remember using it much in my good old Perl days).

该模式text = <<"HERE" This Is A Multiline String HERE在js中不可用(我记得我在Perl的美好时光中经常使用它)。

To keep oversight with complex or long multiline strings I sometimes use an array pattern:

为了对复杂或较长的多行字符串进行监督,有时会使用数组模式:

var myString = 
   ['<div id="someId">',
    'some content<br />',
    '<a href="#someRef">someRefTxt</a>',
    '</div>'
   ].join('\n');

or the pattern anonymous already showed (escape newline), which can be an ugly block in your code:

或已经显示的匿名模式(换行符),这可能是代码中的丑陋块:

 var myString = 
       '<div id="someId"> \
some content<br /> \
<a href="#someRef">someRefTxt</a> \
</div>';

Here’s another weird but working 'trick’1:

这是另一个奇怪但有效的“技巧” 1:

var myString = (function () {
    
    /*
   <div id="someId">
     some content<br />
     <a href="#someRef">someRefTxt</a>
    </div>        
*/}).toString().match(/[^]*\/\*([^]*)\*\/\}$/)[1];

ES20xx supports spanning strings over multiple lines using template strings:

ES20xx支持使用模板字符串跨越多行字符串

let str = `This is a text
    with multiple lines.
    Escapes are interpreted,
    \n is a newline.`;
let str = String.raw`This is a text
    with multiple lines.
    Escapes are not interpreted,
    \n is not a newline.`;

1 Note: this will be lost after minifying/obfuscating your code

1注意:缩小/混淆代码后,这将会丢失

A-4

141

I came up with this very jimmy rigged method of a multi lined string. Since converting a function into a string also returns any comments inside the function you can use the comments as your string using a multilined comment /**/. You just have to trim off the ends and you have your string.

我想出了多行字符串的这种非常笨拙的操纵方法。由于将函数转换为字符串还会返回函数内部的任何注释,因此您可以使用多行注释/ ** /将注释用作字符串。您只需要修剪两端就可以了。

var myString = function(){
    
    /*
    This is some
    awesome multi-lined
    string using a comment 
    inside a function 
    returned as a string.
    Enjoy the jimmy rigged code.
*/}.toString().slice(14,-3)

alert(myString)

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转载自blog.csdn.net/SmallTeddy/article/details/108724873