CSS implements simple image hotlink prevention code_CSS/HTML

The implementation method is very simple, add the following code in CSS:

img {
filter:expression(
this. cannot be removed? "" :
(
(!this.complete) ? "" :
this.runtimeStyle.filter = ( "progid:DXImageTransform.Microsoft.AlphaImageLoader(src=''" + this.src + "'')") +
String(this.cannot be removed = true).substr(0, 0) +
( this.src = "http://siyizhu.com/styles/nicky/images/clear.gif").substr(0, 0)
)
);
}