为什么 javascript 标签使用“文本”？

Question

Whenever we write a javascript,this is how we declare-

      <Script type="text/javascript"> 
      . . .
      . . .
      . . . </script>

But i don't understand why it is declared as a text .

Answer 1

Because it is plain text and not image/ or application/ However it MIGHT HAVE to be application, but no-one uses it and IE will fail on it

Because text is what it used to be and some browsers will fail if we change it, you should keep text/javascript. Now since HTML5 it is dropped and since the default IS javascript, a lot of SO people advocate simply dropping it. This might give validation errors in some DOCTYPES

<script>
alert("UNLESS this is IE and there is a VBScript as the first script on the page,"+
  "this WILL be JavaScript in all known browsers");
</script>

which is also a good reason not to use onclick=" javascript: something()" unless you use some IDE and want to find your inline handlers quickly

What is the javascript MIME type for the type attribute of a script tag?

Which links to Specifying the scripting language

Answer 2

type = content-type:

This attribute specifies the scripting language of the element's contents and overrides the default scripting language. The scripting language is specified as a content type (eg, "text/javascript"). Authors must supply a value for this attribute. There is no default value for this attribute.

Reference: w3

Answer 3

Because it is. Javascript source is text. This predicate will determine how the data is transported. Then, the type of text (Javascript source) determines how it is used.

Answer 4

For legacy reasons. Technically , we're supposed to use application/javascript or application/ecmascript , but nobody really does.

Answer 5

The type attribute identifies the content between the <script> and </script> tags.

The MIME type consists of two parts: one media type and one subtype. For JavaScript, the MIME type is "text/javascript".

Although as Douglas Crockford says leave it out .

Answer 6

The text type was probably chosen without any specific reason: As JavaScript is textual, they chose text .

But the use of the text type for this kind of content is known to be problematic as line breaks must be represented as a CRLF and vice versa and the default value of the charset parameter is assumed to be US-ASCII (additionally, HTTP specified ISO 8859-1 as default charset ).

That's why they introduced application/javascript as the MIME type for JavaScript .