Wordpress网站内部页面中的条件重定向问题

I have one website www.example.com it has 5 pages lets say

www.example.com
www.example.com/about-us
www.example.com/terms-of-use
www.example.com/privacy-policy
www.example.com/apps

Now in the last page which is www.example.com/apps, I want following code to be executed in apps landing page:

    $user_agent = $_SERVER['HTTP_USER_AGENT'];

    if(strpos($user_agent, "Win") !== FALSE){
        $url = "http://www.example.com";
    }elseif(strpos($user_agent, "Mac") !== FALSE){
        $url = "https://itunes.apple.com/us/app/exmaple/idwewew?ls=1&mt=8";
    }elseif(strpos($user_agent, "Android") !== FALSE){
        $url = "https://play.google.com/store/apps/details?id=com.example"; 
    }
    wp_redirect($url, 302); exit;

Which means If user access this page from windows device it will redirect user to home page, if user access this page from android device then goes to google play store and similarly for iOS device...

Now when I put this code in edit page, it wont work...I am using PHP Code Widget plugin

Please help...

Try doing something like this (without PHP Code Widget at all):

// functions.php

function my_page_template_redirect()
{
    if ( is_page( 'apps' ) )
    {
        $user_agent = $_SERVER['HTTP_USER_AGENT'];

        if ( strpos( $user_agent, "Win" ) !== false ) {
            $url = "http://www.example.com";
        } elseif ( strpos( $user_agent, "Mac" ) !== false ) {
            $url = "https://itunes.apple.com/us/app/exmaple/idwewew?ls=1&mt=8";
        } elseif ( strpos( $user_agent, "Android" ) !== false ){
            $url = "https://play.google.com/store/apps/details?id=com.example"; 
        }
        wp_redirect( $url, 302 );
        exit();
    }
}
add_action( 'template_redirect', 'my_page_template_redirect' );

P.S. I didn't test this code, so, please let me know how it works for you.