window.location.search.substring(1)

window.location.search.substring(1);

The function is to get the specified parameters after the current page GET request?, for example, the passed GET request is  "test.html?name=22&id=11"

Then call the function on the current page 

var lsw=window.location.search.substring(1);

// The value of lsw is  name=22&id=11