微信APIV3签名错误，有偿

Question

{"detail":{"issue":"sign not match"},"field":"signature","location":"authorization","sign_information":{"method":"POST","sign_message_length":391,"truncated_sign_message":"POST\n/v3/transfer/batches\n1717829597\n2683f6ac0bf44dcfb2b3ffa3a0d81865\n{\"appid\"\n","url":"/v3/transfer/batches"}},"message":"错误的签名，验签失败"}

加V：y00100594131，有偿200

Answer 1

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看起来你在尝试使用微信支付API V3进行转账操作时遇到了签名验证失败的问题。根据错误信息，微信服务器返回的消息指出签名不匹配（sign not match）。为了帮您解决这个问题，我们需要检查几个关键点：

1. 确保您的密钥对是正确的。
2. 检查请求方法、URL、请求体以及时间戳是否正确地用于签名计算。
3. 使用正确的签名算法（SHA256）。

下面是一个C#示例代码，展示了如何构建并验证签名。请注意，你需要将YOUR_APPID、YOUR_API_KEY替换为实际的AppID和API Key。

using System;
using System.Collections.Generic;
using System.IO;
using System.Net.Http;
using System.Text;
using System.Threading.Tasks;
using Newtonsoft.Json;

public class WeChatPayHelper
{
    private const string BaseUrl = "https://api.mch.weixin.qq.com";
    private readonly string _appId;
    private readonly string _apiKey;

    public WeChatPayHelper(string appId, string apiKey)
    {
        _appId = appId;
        _apiKey = apiKey;
    }

    public async Task<string> SendRequestAsync(HttpMethod method, string path, Dictionary<string, object> data)
    {
        var timestamp = GetTimestamp();
        var nonceStr = GenerateNonceStr();

        var url = $"{BaseUrl}/{path}";
        var sortedParameters = GetSortedParameters(method, timestamp, nonceStr, data);
        var sign = CalculateSignature(sortedParameters);

        var content = new StringContent(JsonConvert.SerializeObject(data), Encoding.UTF8, "application/json");
        using var httpClient = new HttpClient();
        httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", sign);
        httpClient.DefaultRequestHeaders.TryAddWithoutValidation("Timestamp", timestamp);
        httpClient.DefaultRequestHeaders.TryAddWithoutValidation("NonceStr", nonceStr);

        var response = await httpClient.SendAsync(new HttpRequestMessage(method, url) { Content = content });

        if (response.IsSuccessStatusCode)
        {
            var responseBody = await response.Content.ReadAsStringAsync();
            return responseBody;
        }
        else
        {
            throw new Exception($"HTTP error: {(int)response.StatusCode} - {response.ReasonPhrase}");
        }
    }

    private static long GetTimestamp()
    {
        return DateTimeOffset.UtcNow.ToUnixTimeSeconds();
    }

    private static string GenerateNonceStr()
    {
        return Guid.NewGuid().ToString("N").Substring(0, 16);
    }

    private static string CalculateSignature(Dictionary<string, string> parameters)
    {
        var sortedKeys = parameters.Keys.OrderBy(key => key).ToList();
        var sb = new StringBuilder();
        foreach (var key in sortedKeys)
        {
            sb.Append($"{key}={parameters[key]}&");
        }
        sb.Append("key=" + _apiKey); // 添加API Key到参数末尾

        var plainText = sb.ToString();
        var hashBytes = Encoding.UTF8.GetBytes(plainText);
        using var sha256 = System.Security.Cryptography.SHA256.Create();
        var hash = sha256.ComputeHash(hashBytes);
        return Convert.ToBase64String(hash);
    }

    private static Dictionary<string, string> GetSortedParameters(HttpMethod method, long timestamp, string nonceStr, Dictionary<string, object> data)
    {
        var parameters = new Dictionary<string, string>
        {
            {"mch_id", _appId},
            {"nonce_str", nonceStr},
            {"timestamp", timestamp.ToString()},
            {"sign_method", "HMAC-SHA256"},
        };

        foreach (var kvPair in data)
        {
            parameters.Add(kvPair.Key, kvPair.Value.ToString());
        }

        return parameters;
    }
}

// 示例用法
public async Task Main()
{
    var helper = new WeChatPayHelper("YOUR_APPID", "YOUR_API_KEY");
    var data = new Dictionary<string, object>
    {
        {"appid", "YOUR_APPID"}, // 请确保这个字段在数据中
        // 其他需要传递的数据...
    };
    var result = await helper.SendRequestAsync(HttpMethod.Post, "/v3/transfer/batches", data);
    Console.WriteLine(result);
}

请确保你的AppID和API Key是有效的，并且在调用SendRequestAsync方法时，提供的数据包含了所有必要的字段，特别是appid。此外，确保所有请求头的时间戳和随机字符串都是新的，每次请求都应使用不同的nonce_str。

如果问题仍然存在，请检查网络请求和响应内容，确保没有遗漏任何关键信息。如果你还有其他疑问或遇到其他问题，随时向我提问。