题意：为什么 OpenAI 图像生成 API 在 Unity 中返回 400 Bad Request 错误？

问题背景：

I'm testing out dynamically generating images using OpenAI API in Unity. Amusingly, I actually generated most of this code from chatGPT.

我正在测试在 Unity 中使用 OpenAI API 动态生成图像。有趣的是，我实际上是通过 ChatGPT 生成了大部分代码。

The Error response is: "Your request contained invalid JSON: Expecting value: line 1 column 1 (char 0)". But I cant see anything wrong with the json formatting of my requestbody...

错误响应是：‘你的请求包含无效的 JSON：期待值：第 1 行第 1 列 (字符 0)’。但我看不出我的请求体的 JSON 格式有什么问题……

I also found this other question which is probably failing for the same reason, whatever it is: 

我还发现了另一个问题，可能因为同样的原因而失败，无论是什么原因：Why does Post request to OpenAI in Unity result in error 400?

Here is my code:        以下是我的代码：

public class PlayerScript : MonoBehaviour
{
    // Replace API_KEY with your actual API key
    private string API_KEY = "<api_key>";
    private string API_URL = "https://api.openai.com/v1/images/generations";

    void Start()
    {
        StartCoroutine(GetImage());
    }

    IEnumerator GetImage()
    {
        // Create a request body with the prompt "Player"
        string requestBody = "{\"prompt\": \"Player\",\"n\": 1,\"size\": \"128x128\"}";
        // Create a UnityWebRequest and set the request method to POST
        UnityWebRequest www = UnityWebRequest.Post(API_URL, requestBody);

        // Set the authorization header with the API key
        www.SetRequestHeader("Authorization", "Bearer " + API_KEY);

        // Set the content type header
        www.SetRequestHeader("Content-Type", "application/json");

        // Send the request
        yield return www.SendWebRequest();

        // Check for errors
        if (www.isNetworkError || www.isHttpError)
        {
            Debug.LogError(www.error);
        }
        else
        {
            // do stuff
        }
    }
}

Any idea what's going wrong? Apologies if it's something obvious, never made web requests in Unity before.

知道哪里出了问题吗？如果问题显而易见请见谅，我以前从未在 Unity 中发过网络请求。

问题解决：

UnityWebRequests url-encodes content before submitting the request. This messes up the formatting. see: 

UnityWebRequests 在提交请求之前会对内容进行 URL 编码，这会导致格式混乱。参见：prevent UnityWebRequest.Post() from Url-Encoding the data ? - Questions & Answers - Unity Discussions

using httpClient worked for me.

“使用 httpClient 对我来说是有效的。