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Unity C# 之 使用 HttpWebRequest 基础知识/HttpWebRequest 进行异步Post 网络访问/数据流形式获取数据(Task/async/await)的代码简单实现
目录
Unity C# 之 使用 HttpWebRequest 基础知识/HttpWebRequest 进行异步Post 网络访问/数据流形式获取数据(Task/async/await)的代码简单实现
2、HttpWebRequest 中的 ContentType
4、HttpWebRequest json 文本 Post 请求示例
5、 HttpWebRequest multipart/form-data 文件上传示例
一、简单介绍
Unity 在开发中，网络访问：
- 可以使用 UnityWebRequest 访问，不过好似只能用协程的方式，并且访问只能在主线程中；
- 所以这里使用 C# 中的 HttpWebRequest，进行网络访问，而且 HttpWebRequest，允许在子线程中访问，在一些情况下可以大大减少主线程的网络访问压力；
这里使用 HttpWebRequest ，进行 Post 访问，并且Task 结合 async （await） 的进行异步访问，最后使用 Stream 流式的形式获取数据，在这里做一个简单的记录，以便后期使用的时候参考。
二、实现原理
1、HttpWebRequest 创建 post 的请求
2、GetRequestStreamAsync 发起 异步请求
3、GetResponseAsync 和 GetResponseStream 异步获取响应数据流
4、因为使用到异步，所以 async Task<string> 返回异步获取的流数据
三、注意事项
1、获取更新的流数据打印是，注意 每次更新下 buffer ，不然输出打印的结果可能不是预期的
// 循环获取流式数据 while ((bytesRead = await reader.ReadAsync(buffer, 0, buffer.Length)) > 0) { sb.Append(buffer, 0, bytesRead); Console.WriteLine(buffer); buffer = new char[1024]; }四、效果预览
五、关键代码
using System; using System.Net; using System.Text; namespace TestHttpWebRequestPostStream { internal class Program { static string m_Authorization = "Your_Authorization"; static int TIMEOUT_TIME = 10000; // 超时时间 static async Task Main(string[] args) { string url = "Your_STREAM_URL"; string postData = "Your_POST_DATA"; string content = await PostRequestStreamToStringAsync(url, postData); Console.WriteLine("Response content:"); Console.WriteLine(content); } static async Task<string> PostRequestStreamToStringAsync(string url, string postData) { try { HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest; request.ReadWriteTimeout = TIMEOUT_TIME; request.Timeout = TIMEOUT_TIME; request.Method = "POST"; request.ContentType = "application/json"; // 根据需要设定 request.Headers.Add("user-token", "xxxxxxxx"); // 根据需要设定 request.Headers.Add("xxxx-authorization", m_Authorization); // 根据需要设定 //流式发起请求 using (Stream requestStream = await request.GetRequestStreamAsync()) { byte[] dataBytes = Encoding.UTF8.GetBytes(postData); await requestStream.WriteAsync(dataBytes, 0, dataBytes.Length); } // 流式获取数据响应 using (HttpWebResponse response = (HttpWebResponse)await request.GetResponseAsync()) using (Stream responseStream = response.GetResponseStream()) using (StreamReader reader = new StreamReader(responseStream)) { StringBuilder sb = new StringBuilder(); char[] buffer = new char[1024]; int bytesRead; // 循环获取流式数据 while ((bytesRead = await reader.ReadAsync(buffer, 0, buffer.Length)) > 0) { sb.Append(buffer, 0, bytesRead); Console.WriteLine(buffer); buffer = new char[1024]; } return sb.ToString(); } } catch (Exception e) { return e.Message; } } } }附录 ： HttpWebRequest 的一些基础知识
1、HttpWebRequest 常用属性
- AllowAutoRedirect：获取或设置一个值，该值指示请求是否应跟随重定向响应。
- CookieContainer：获取或设置与此请求关联的cookie。
- Credentials：获取或设置请求的身份验证信息。
- KeepAlive：获取或设置一个值，该值指示是否与 Internet 资源建立持久性连接。
- MaximumAutomaticRedirections：获取或设置请求将跟随的重定向的最大数目。
- Proxy：获取或设置请求的代理信息。
- SendChunked：获取或设置一个值，该值指示是否将数据分段发送到 Internet 资源。
- Timeout：获取或设置请求的超时值。
- UserAgent：获取或设置 User-agent HTTP 标头的值
- ContentType：Http内容类型
- Headers：指定组成 HTTP 标头的名称/值对的集合。
2、HttpWebRequest 中的 ContentType
- 普通文本: “text/plain”
- JSON字符串: “application/json”
- 数据流类型(文件流): “application/octet-stream”
- 表单数据(键值对): “application/x-www-form-urlencoded”
- 多分部数据: “multipart/form-data”
3、HttpWebRequest 一般使用示例
//创建HttpWeb请求 HttpWebRequest request = (HttpWebRequest)WebRequest.Create (url); //创建HttpWeb相应 HttpWebResponse response = (HttpWebResponse)request.GetResponse (); Console.WriteLine ("Content length is {0}", response.ContentLength); Console.WriteLine ("Content type is {0}", response.ContentType); //获取response的流 Stream receiveStream = response.GetResponseStream (); //使用streamReader读取流数据 StreamReader readStream = new StreamReader (receiveStream, Encoding.UTF8); Console.WriteLine ("Response stream received."); Console.WriteLine (readStream.ReadToEnd ()); response.Close (); readStream.Close (); 4、HttpWebRequest json 文本 Post 请求示例
使用application/json作为请求头，用来告诉服务端消息主体是序列化的JSON字符串。
/* * url:POST请求地址 * postData:json格式的请求报文,例如：{"key1":"value1","key2":"value2"} */ public static string PostUrl(string url, string postData) { HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url); req.Method = "POST"; req.TimeOut = "800";//设置请求超时时间，单位为毫秒 req.ContentType = "application/json"; byte[] data = Encoding.UTF8.GetBytes(postData); req.ContentLength = data.Length; using (Stream reqStream = req.GetRequestStream()) { reqStream.Write(data, 0, data.Length); reqStream.Close(); } HttpWebResponse resp = (HttpWebResponse)req.GetResponse(); Stream stream = resp.GetResponseStream(); //获取响应内容 string result = ""; using (StreamReader reader = new StreamReader(stream, Encoding.UTF8)) { result = reader.ReadToEnd(); } return result; } 5、 HttpWebRequest multipart/form-data 文件上传示例
使用multipart/form-data作为请求头，用来告诉服务器消息主体是 多发文件 格式
multipart/form-data格式使用一长串字符作为boundtry封装线对字段进行分割。这也很符合multipart多个部分的语义，包含了多个部分集，每一部分都包含了一个content-desposition头，其值为form-data,以及一个name属性，其值为表单的字段名，文件输入框还可以使用filename参数指定文件名。content-type非必须属性，其值会根据文件类型进行变化，默认值是text/plain。multipart的每一个part上方是边界线，最后一个part的下方添加一个边界线。
/// <summary> /// 上传文件请求 /// </summary> /// <param name="url">Url</param> /// <param name="filePath">文件路径</param> /// <param name="formDatas">表单数据（字典格式）</param> /// <param name="callback">上传回调</param> public static void UploadRequest(string url, string filePath, Dictionary<string,string> formDatas, Action<string> callback) { // 时间戳，用做boundary string timeStamp = DateTime.Now.Ticks.ToString("x"); //根据uri创建HttpWebRequest对象 HttpWebRequest httpReq = (HttpWebRequest) WebRequest.Create(new Uri(url)); httpReq.Method = "POST"; httpReq.AllowWriteStreamBuffering = false; //对发送的数据不使用缓存 httpReq.Timeout = 300000; //设置获得响应的超时时间（300秒） httpReq.ContentType = "multipart/form-data; boundary=" + timeStamp; //读取file文件 FileStream fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read); BinaryReader binaryReader = new BinaryReader(fileStream); //表单信息 string boundary = "--" + timeStamp; string form = ""; string formFormat = boundary + "\r\nContent-Disposition: form-data; name=\"{0}\"\r\n\r\n{1}\r\n"; string formEnd = boundary + "\r\nContent-Disposition: form-data; name=\"{0}\"; filename=\"{1}\";\r\nContent-Type:application/octet-stream\r\n\r\n"; foreach (var pair in formDatas) { form += string.Format(formFormat, pair.Key, pair.Value); } form += string.Format(formEnd,"file", Path.GetFileName(filePath)); byte[] postHeaderBytes = Encoding.UTF8.GetBytes(form); //结束边界 byte[] boundaryBytes = Encoding.ASCII.GetBytes("\r\n--" + timeStamp + "--\r\n"); long length = fileStream.Length + postHeaderBytes.Length + boundaryBytes.Length; httpReq.ContentLength = length; //请求内容长度 try { //每次上传4k int bufferLength = 4096; byte[] buffer = new byte[bufferLength]; //已上传的字节数 long offset = 0; int size = binaryReader.Read(buffer, 0, bufferLength); Stream postStream = httpReq.GetRequestStream(); //发送请求头部消息 postStream.Write(postHeaderBytes, 0, postHeaderBytes.Length); while (size > 0) { postStream.Write(buffer, 0, size); offset += size; size = binaryReader.Read(buffer, 0, bufferLength); } //添加尾部边界 postStream.Write(boundaryBytes, 0, boundaryBytes.Length); postStream.Close(); //获取服务器端的响应 using (HttpWebResponse response = (HttpWebResponse) httpReq.GetResponse()) { Stream receiveStream = response.GetResponseStream(); StreamReader readStream = new StreamReader(receiveStream, Encoding.UTF8); string returnValue = readStream.ReadToEnd(); Debug.Log("upload result:"+returnValue); callback?.Invoke(returnValue); response.Close(); readStream.Close(); } } catch (Exception ex) { Debug.Log("文件传输异常： " + ex.Message); } finally { fileStream.Close(); binaryReader.Close(); } } Unity 上的简单的异步封装使用
1、HttpWebRequest 异步 Post 获取数据
using System; using System.IO; using System.Net; using System.Text; using System.Threading.Tasks; using UnityEngine; public class GptNormalWrapper : Singleton<GptNormalWrapper>, IGptHttpWebRequestWrapper { const string GPT_URL = "Your_URL"; const string AUTHORIZATION = "Your_AUTHORIZATION"; const string USER_TOKEN = "123456"; const int TIMEOUT_TIME = 10000; // 超时时间 public string GptUrl => GPT_URL; public async Task<string> PostRequestToStringAsync(string postData) { return await PostRequestToStringAsync(GptUrl, postData); } public async Task<string> PostRequestToStringAsync(string url, string postData) { try { HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest; request.ReadWriteTimeout = TIMEOUT_TIME; request.Timeout = TIMEOUT_TIME; request.Method = "POST"; request.ContentType = "application/json"; request.Headers.Add("user-token", USER_TOKEN); request.Headers.Add("xxx-authorization", AUTHORIZATION); Debug.Log("[GptNormalWrapper] PostRequestToStringAsync msg = " + postData); byte[] jsonBytes = Encoding.UTF8.GetBytes(postData); request.ContentLength = jsonBytes.Length; Stream strStream = request.GetRequestStream(); strStream.Write(jsonBytes, 0, jsonBytes.Length); strStream.Close(); HttpWebResponse respone = (HttpWebResponse)await request.GetResponseAsync(); Stream ns = respone.GetResponseStream(); string responseContent = new StreamReader(ns, Encoding.UTF8).ReadToEnd(); Debug.Log("[GptNormalWrapper] PostRequestToStringAsync 消息返回:" + responseContent); MessageBack textback = JsonUtility.FromJson<MessageBack>(responseContent); Debug.Log($"[GptNormalWrapper] PostRequestToStringAsync answer content {textback.data.choices[0].message.content} "); return new(textback.data.choices[0].message.content); } catch (Exception e) { Debug.LogError("[GptNormalWrapper] PostRequestToStringAsync error:" + e); } return new(GptChatCommonStringDefine.GPT_REQUEST_SERVER_FAILED); } } 2、HttpWebRequest 异步 Post 流式的获取数据
using System.Net; using System.Threading.Tasks; using System.Text; using System.IO; using UnityEngine; using System; public class GptStreamWrapper : Singleton<GptStreamWrapper>, IGptHttpWebRequestWrapper { const string GPT_URL = "Your_URL"; const string AUTHORIZATION = "Your_AUTHORIZATION"; const string USER_TOKEN = "123456"; const int TIMEOUT_TIME = 10000; // 超时时间 public string GptUrl { get; } = GPT_URL; public async Task<string> PostRequestToStringAsync(string postData) { return await PostRequestToStringAsync(GptUrl, postData); } public async Task<string> PostRequestToStringAsync(string url, string postData) { try { HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest; request.ReadWriteTimeout = TIMEOUT_TIME; request.Timeout = TIMEOUT_TIME; request.Method = "POST"; request.ContentType = "application/json"; request.Headers.Add("user-token", USER_TOKEN); request.Headers.Add("xxx-authorization", AUTHORIZATION); //流式发起请求 using (Stream requestStream = await request.GetRequestStreamAsync()) { Debug.Log("[GptStreamWrapper] PostRequestStreamToStringAsync postData : " + postData); byte[] dataBytes = Encoding.UTF8.GetBytes(postData); await requestStream.WriteAsync(dataBytes, 0, dataBytes.Length); } // 流式获取数据响应 using (HttpWebResponse response = (HttpWebResponse)await request.GetResponseAsync()) using (Stream responseStream = response.GetResponseStream()) using (StreamReader reader = new StreamReader(responseStream)) { StringBuilder sb = new StringBuilder(); char[] buffer = new char[1024]; int bytesRead; // 循环获取流式数据 while ((bytesRead = await reader.ReadAsync(buffer, 0, buffer.Length)) > 0) { sb.Append(buffer, 0, bytesRead); Debug.Log("[GptStreamWrapper] PostRequestStreamToStringAsync getting steam data : " + buffer); buffer = new char[1024]; } Debug.Log("[GptStreamWrapper] PostRequestStreamToStringAsync whole stream data : " + sb.ToString()); return sb.ToString(); } } catch (Exception e) { Debug.Log("[GptStreamWrapper] PostRequestStreamToStringAsync Exception Message data : " + e.Message); return new(GptChatCommonStringDefine.GPT_REQUEST_SERVER_FAILED); } } } 