1. A large part of the reason why browsers prohibit cross-domain is to prevent XSS attacks. If you turn on cross-domain prohibition in the browser, you can cross-domain. So it does not mean that ajax or jquery is not allowed, but that it is prohibited by the browser 2. iOS applications cannot carry out XSS attacks, so there are no restrictions. 3. When you access HTML-structured web pages in Android or iOS webview, there should also be cross-domain restrictions.
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1. A large part of the reason why browsers prohibit cross-domain is to prevent XSS attacks. If you turn on cross-domain prohibition in the browser, you can cross-domain. So it does not mean that ajax or jquery is not allowed, but that it is prohibited by the browser
2. iOS applications cannot carry out XSS attacks, so there are no restrictions. 3. When you access HTML-structured web pages in Android or iOS webview, there should also be cross-domain restrictions.