ExampleUse of the <noscript> tag: <script type="text/javascript"> document.write("Hello World!") </script> <noscript>Your browser does not support JavaScript!</noscript> <script type="text/vbscript"> Sub edit1_changed() If edit1.value = "abc" Then button1.enabled = True Else button1.enabled = False End If End Sub </script> <noscript>Your browser does not support VB Script!</noscript> | Browser Support |
1. Definition and Usage
The <noscript> tag is used to provide an alternate content for users that have disabled scripts in their browser or have a browser that doesn't support client-side scripting.
The <noscript> element can contain all the elements that you can find inside the <body> element of a normal HTML page.
The content inside the <noscript> element will only be displayed if scripts are not supported, or are disabled in the user's browser.
2. Tips and Notes
Tip: It is also a good practice to use the comment tag to "hide" scripts from browsers without support for client-side scripts (so they don't show them as plain text):
<!--
function displayMsg()
{
alert("Hello World!")
}
//-->
</script>
3. Differences Between HTML and XHTML
None
4. Standard Attributes
DTD indicates in which HTML 4.01/XHTML 1.0 DTD the attribute is allowed. S=Strict, T=Transitional, and F=Frameset.
The <noscript> tag supports the following standard attributes:
| Attribute | Value | Description | DTD |
|---|---|---|---|
| class | classname | Specifies a classname for an element | STF |
| dir | rtl ltr | Specifies the text direction for the content in an element | STF |
| id | id | Specifies a unique id for an element | STF |
| lang | language_code | Specifies a language code for the content in an element | STF |
| style | style_definition | Specifies an inline style for an element | STF |
| title | text | Specifies extra information about an element | STF |
| xml:lang | language_code | Specifies a language code for the content in an element, in XHTML documents | STF |
5. Event Attributes
According to the W3C standard, the <noscript> tag supports event attributes. However, since the noscript element is used to provide an alternate content for users that have disabled scripts, we cannot see any use for this.
| Attribute | Value | Description | DTD |
|---|---|---|---|
| onclick | script | Script to be run on a mouse click | STF |
| ondblclick | script | Script to be run on a mouse double-click | STF |
| onmousedown | script | Script to be run when mouse button is pressed | STF |
| onmousemove | script | Script to be run when mouse pointer moves | STF |
| onmouseout | script | Script to be run when mouse pointer moves out of an element | STF |
| onmouseover | script | Script to be run when mouse pointer moves over an element | STF |
| onmouseup | script | Script to be run when mouse button is released | STF |
| onkeydown | script | Script to be run when a key is pressed | STF |
| onkeypress | script | Script to be run when a key is pressed and released | STF |
| onkeyup | script | Script to be run when a key is released | STF |
