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using System; using System.Net.Http; using System.Text; using System.Collections.Generic; using System.Threading.Tasks; using System.Threading; public class VipSoftHttpHelper { private readonly HttpClient _httpClient; private VipSoftHttpHelper() { _httpClient = new HttpClient(new HttpClientHandler() { UseProxy = false, // 其他配置... }); _httpClient.DefaultRequestHeaders.Add("User-Agent", "C#-Client"); } private static readonly Lazy<VipSoftHttpHelper> instance = new Lazy<VipSoftHttpHelper>(() => new VipSoftHttpHelper()); public static VipSoftHttpHelper Instance => instance.Value; /// <summary> /// POST 请求 Java API 接口 /// </summary> /// <param name="url">请求地址</param> /// <param name="postData">请求数据对象</param> /// <param name="timeoutSeconds">超时时间（秒）</param> /// <param name="headers">请求头</param> /// <returns>响应字符串</returns> public string HttpPost(string url, object postData, int timeoutSeconds = 30, Dictionary<string, object> headers = null) { try { // 序列化数据 string jsonContent = Newtonsoft.Json.JsonConvert.SerializeObject(postData); LogHelper.Debug($"HTTP POST: {url}, Timeout: {timeoutSeconds}s, Data: {jsonContent}"); // 使用 HttpRequestMessage 而不是直接修改 HttpClient var request = new HttpRequestMessage(HttpMethod.Post, url) { Content = new StringContent(jsonContent, Encoding.UTF8, "application/json") }; // 添加自定义请求头到本次请求 if (headers != null) { foreach (var header in headers) { if (header.Key.ToLower() == "content-type") continue; request.Headers.TryAddWithoutValidation(header.Key, header.Value); }