# 开发指南

微信支付API v3是基于HTTPS协议的。HTTPS提供了微信支付服务器的身份认证，并保护传输数据的私密性和完整性。但在接收到商户请求时，微信支付仍需要确认三个关键问题：

1. 是哪一个商户发给微信支付的请求
2. 请求的内容是否是第三方伪造
3. 请求的内容是否被中间人篡改

为了保证交易的安全性，微信支付API v3使用了SHA256 with RSA签名，作为请求和应答报文的身份确认和数据校验。在以下的文档中，我们介绍了如何构造一个携带签名的请求和如何验证微信支付API v3应答的签名。


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# Agent Instructions: Querying This Documentation

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Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
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```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.