javascript 注释

Like other programming languages, in JavaScript comments can be used to prevent the execution of the statements. Whenever we want to ignore the statements or any text/document from execution, we use comments.

像其他编程语言一样， JavaScript注释可用于阻止执行语句。 每当我们想要忽略语句或执行中的任何文本/文档时，我们都会使用注释。

For example: While writing the code, sometimes the logic is complex and we want to explain in our words so that we can understand the logic – we can put the explanation in the comments.

例如：在编写代码时，有时逻辑很复杂，我们想用文字解释，以便我们可以理解逻辑–可以将解释放在注释中。

There are two types of comments in JavaScript:

JavaScript有两种类型的注释 ：

1. Single line comment

   单行注释

2. Multi line comments

   多行注释

JavaScript单行注释 (JavaScript single line comment)

For single line comment in JavaScript, we use double slash characters (//) before the text/code. The code/text written after the double slash (//) will be ignored by the interpreter.

对于JavaScript中的单行注释，我们在文本/代码之前使用双斜杠(//)。 解释器将忽略双斜杠(//)之后编写的代码/文本。

Syntax:

句法：

    //This text will not be executed/ interpreted

Example:

例：

<script>
	document.write("This is line1<br>");
	//document.write("This is line2<br>");
	document.write("This is line3<br>");
	//document.write("This is line4<br>");
	document.write("This is line5<br>");
</script>

Output

输出量

This is line1
This is line3
This is line5

JavaScript多行注释 (JavaScript multi line comment)

Multi-line comments can be placed between /* and */. The comment starts with /* and terminates with */. We can place any number of lines between these comment characters.

多行注释可以放在/ *和* /之间。 注释以/ *开头，以* /结束。 我们可以在这些注释字符之间放置任意数量的行。

Syntax:

句法：

    /* 
    This line will not be executed/ interpreted
    This line will also not be executed/ interpreted
    This line will also not be executed/ interpreted
    */

Example:

例：

<script>
	document.write("This is line1<br>");
	/*document.write("This is line2<br>");
	document.write("This is line3<br>");*/
	document.write("This is line4<br>");
	/*
	document.write("This is line5<br>");
	document.write("This is line6<br>");
	document.write("This is line7<br>");
	*/
	document.write("This is line8<br>");
	document.write("This is line9<br>");		
</script>

Output

输出量

This is line1
This is line4
This is line8
This is line9

在语句中注释代码 (Comment the code in a statement)

We can comment on any code in a statement by using multi-line characters.

我们可以使用多行字符对语句中的任何代码进行注释。

Example:

例：

<script>
	document.write("This is line1<br>");
	document.write("This is line2<br>");
	document.write(/*"This is line3<br>"*/"Hello world<br>");
	var result = /*a-b*/ 10-2;
	document.write("result: " + result + "<br>");
</script>

Output

输出量

This is line1
This is line2
Hello world
result: 8

翻译自: https://www.includehelp.com/code-snippets/comments-in-javascript.aspx

javascript 注释