The combined use of Javascript and select components in php

//Combined use of javascript and select components
//In the process of writing the program, I want to realize that after selecting the option in the select object,
//No need to submit button, but trigger the action directly, and after the action occurs
//The selected options should be kept on the page. After describing it, I finally passed it
//Use Javascript and the onchange attribute of the select object and
//value value realizes this function.
//The code is as follows (the file name is "test.php"):


switch ($mon){
case '': echo 'Please select your zodiac sign:';break;
case '1':echo 'Your zodiac sign is Aquarius';break;
Case '2':echo 'Your zodiac sign is Pisces';break;
case '3':echo 'Your zodiac sign is Aries';break;
case '4':echo 'Your zodiac sign is Taurus';break;
case '5':echo 'Your zodiac sign is Gemini';break;
case '6':echo 'Your zodiac sign is Cancer';break;
case '7':echo 'Your zodiac sign is Leo';break;
case '8':echo 'Your zodiac sign is Virgo';break;
case '9':echo 'Your zodiac sign is Libra';break;
case '10':echo 'Your zodiac sign is Scorpio';break;
case '11':echo 'Your zodiac sign is Sagittarius';break;
case '12':echo 'Your zodiac sign is Capricorn';break;
​​default:break;
}        
?>

onChange="javascript:location.href=
This.options[this.selectedIndex].value">
--Please select your zodiac sign--
​​​ >Aquarius
​​​ >Pisces
​​​ >Aries
​​​ >Taurus
​​​ >Gemini
​​​ >Cancer
​​​ >Leo
​​​ >Virgo
​​​ >Libra
​​​ >Scorpio
​​​ >Sagittarius
​​​ >Capricorn

​​​​​

The above introduces the combined use of Javascript and select components in PHP, including aspects of the content. I hope it will be helpful to friends who are interested in PHP tutorials.