HTML does not support static Expando elements _ javascript skills

HTML does not support static Expando elements. When you use scripts to process a batch of pages in a unified manner, I want to obtain the document TITLE and custom attributes through the TITLE element on the processed page. These additional Attributes are added on the server through the Attributes set, but the running results are always far from what I expected, why is the custom attribute I write in the TITLE element always null?

The client and server code are:

ASPX:
Query Info
C #: protected HtmlGenericControl title;

Private void Page_Load (object sender, System. EventArgs e)
{
//...
Title. InnerHtml = "querying information ";
Title. Attributes ["icon"] = "QueryInfo.gif;
}
HTML:
Query Information
JavaScript:
Var iconPath = docucment. all. tags ('title') [0]. icon;
If (iconPath)
{
Var img = document. createElement ('img ');
Img. src = iconPath;
//...
}

The result is the icon that I want from the total topology, tracking JavaScript code, and finding that iconPath is always undefined. Look at the HTML code, which clearly shows the attribute value pair "icon =" QueryInfo.gif. So you can view outerHTML from the title object. outerHTML is: Query Information. There is no icon attribute at all. It is no wonder that iconPath obtained by JavaScript is always undefined.

After careful investigation, we found that html elements differ in processing the expando attribute. There are two ways to add the expando attribute to an html element. One is the common dynamic method. The other is to use a script to add the expando attribute to an html element. The second is to use the static method, that is, to add the expando attribute in literal mode in html code. Examples:

Add the expando attribute dynamically: this is a span element.