<html><head><script src="https://libs.baidu.com/jquery/2.1.4/jquery.min.js"></script><script>$(document).ready(function(){ $("button").click(function(){ $("#ca").attr("href", "https://cankaoshouce.com/jquery/"); });});</script></head><body><p><a href="https://cankaoshouce.com" id="ca">cankaoshouce.com</a></p><button>Change href Value</button><p>Mouse over the link (or click on it) to see that the value of the href attribute has changed.</p></body></html>