Please tell me how to do this prompt from Sohu? _html/css_WEB-ITnose

When I woke up early to watch a video, I found this on Sohu. Could you please tell me what the principle is and how it was written?

Reply to the discussion (solution)

Search on Baidu or Google

Does anyone know?

Many browsers set ctrl d by default to add favorites
You can also use js to write ctrl d to add.
You need to complete two points
1. The function of adding favorites
2. When the user clicks ctrl and d, the above function is called

The original poster searched for relevant content.

Please refer to this article: http://blog.csdn.net/welcomett_com/article/details/7393616

Thanks to the two friends on the third and fourth floors, thank you.