ajax请求地址只支持http/https吗？能做到让它支持rtmp://等其它自定义协议吗 ？

No, standard AJAX requests (using the XMLHttpRequest object or the fetch API) only support HTTP(S) protocols. They are specifically designed for communicating with web servers using these protocols. RTMP (Real-Time Messaging Protocol) is a different type of protocol primarily used for streaming audio, video, and data. You cannot directly use AJAX to make requests to an RTMP URL.

Here are the reasons why and what alternatives you can consider:

• Protocol Design: AJAX relies on HTTP's request-response cycle. RTMP, on the other hand, is a stateful protocol designed for persistent connections and real-time data streaming. This fundamental difference makes them incompatible.
• Browser Security: Browsers enforce strict security policies that limit the protocols AJAX can use to HTTP and HTTPS. This is to protect users from potential security vulnerabilities.
• JavaScript Limitations: JavaScript itself, within the browser environment, doesn't have native support for RTMP.

Alternatives for working with RTMP in the frontend:

1. Flash (deprecated): Historically, Flash was the primary method for handling RTMP in browsers. However, Flash is now deprecated and no longer supported by most browsers.

2. WebSockets: While not directly compatible with RTMP, WebSockets provide a way to establish persistent, bidirectional communication with a server. You could use a server-side component that acts as a bridge between WebSockets and RTMP. Your frontend would communicate with this server via WebSockets, and the server would then handle the RTMP connection.

3. Libraries like flv.js: flv.js is a JavaScript library that can play FLV files directly in the browser without Flash. It parses the FLV format and can handle RTMP streams. This is a good option if you're primarily concerned with playing RTMP-delivered video.

4. Dedicated RTMP players: Consider embedding a dedicated RTMP player (like JW Player or Flowplayer) into your web page. These players often handle the complexities of RTMP streaming.

5. WebRTC: For real-time communication scenarios, WebRTC (Web Real-Time Communication) is a powerful alternative. It allows peer-to-peer communication, including audio and video streaming, without the need for plugins or intermediary servers (though a signaling server is usually required for initial connection establishment). You might need a server-side component to convert RTMP to a WebRTC-compatible format.

In summary, you can't directly use AJAX with RTMP. You'll need to use an alternative approach like a dedicated library, a server-side bridge, or a different real-time communication technology like WebRTC. The best solution depends on the specific requirements of your application.