我如何能使一个HTTP POST请求和发送数据的主体?
当前回答
下面是我在. net 4.8中使用的HTTP POST请求。 使用这段代码,可以一次异步发送多个POST请求。
在每个请求的末尾会引发一个事件。并且在所有请求的末尾会引发另一个事件。
下图是核心类:
Imports System.ComponentModel
Imports System.Text.RegularExpressions
Imports System.Timers
Imports System.Windows.Forms
Imports AeonLabs
Imports AeonLabs.Environment
Imports Newtonsoft.Json
Public Class HttpDataCore
Public Property url As String
Public Property state As New environmentVarsCore
Public Property errorMessage As String = ""
Public Property statusMessage As String
Public Property threadCount As Integer = 25
Public Property numberOfRetryAttempts = 5
Public Property queue As List(Of _queue_data_struct)
Public Property queueBWorker As Integer() ' has the size of threadCount
Public Property queueLock As New Object
Public Property retryAttempts As New _retry_attempts
Public Property dataStatistics As List(Of _data_statistics)
Public Property loadingCounter As Integer
Public Property CompletionPercentage As Integer ' value range 0-100
Public Property IsBusy As Boolean
Public Structure _queue_data_struct
Dim vars As Dictionary(Of String, String)
Dim filenameOrSavePath As String ' full address file name or full adress folder path
Dim misc As Dictionary(Of String, String)
Dim status As Integer ' -1 - completed; 0- not sent yet; 1-already sent / processing
End Structure
Public Structure _retry_attempts
Dim counter As Integer
Dim pattern As Integer
Dim previousPattern As Integer
Dim errorMessage As String
End Structure
Public Structure _data_statistics
Dim filesize As Double
Dim bytesSentReceived As Double
Dim speed As Double
End Structure
Public WithEvents RestartQueueTimer As New Timers.Timer
Public bwDataRequest() As BackgroundWorker
Public Event requestCompleted(sender As Object, requestData As String) 'TODO add misc vars
Private sendToQueue As Boolean
Public Sub New(ByVal Optional _state As environmentVarsCore = Nothing, ByVal Optional _url As String = "")
queue = New List(Of _queue_data_struct)
dataStatistics = New List(Of _data_statistics)
loadingCounter = 0
sendToQueue = False
If _state IsNot Nothing AndAlso _url.Equals("") Then
url = _state.ServerBaseAddr & _state.ApiServerAddrPath
ElseIf Not _url.Equals("") Then
url = _url
Else
Throw New System.Exception("Initialization err: state and url cannot be both null at same time")
End If
If _state IsNot Nothing Then
state = _state
End If
End Sub
Public Sub loadQueue(ByVal vars As Dictionary(Of String, String), ByVal Optional misc As Dictionary(Of String, String) = Nothing, ByVal Optional filenameOrSavePath As String = Nothing)
Dim queueItem As New _queue_data_struct
queueItem.vars = New Dictionary(Of String, String)
queueItem.misc = New Dictionary(Of String, String)
queueItem.vars = vars
queueItem.status = 0
queueItem.misc = misc
queueItem.filenameOrSavePath = filenameOrSavePath
queue.Add(queueItem)
End Sub
Public Sub clearQueue()
loadingCounter = 0
queue = New List(Of _queue_data_struct)
End Sub
Public Sub startRequest()
If bwDataRequest(0) Is Nothing Then
Throw New Exception("You need to call initialze first")
Exit Sub
End If
'startSendQueue()
IsBusy = True
AddHandler RestartQueueTimer.Elapsed, New ElapsedEventHandler(AddressOf QueueTimerTick)
With RestartQueueTimer
.Enabled = True
.Interval = 500
.Start()
End With
End Sub
Private Sub QueueTimerTick(ByVal sender As Object, ByVal e As ElapsedEventArgs)
If QueuesToComplete(queue).Equals(0) And QueuesToSend(queue).Equals(0) Then
RestartQueueTimer.Stop()
queue = New List(Of _queue_data_struct)
RaiseEvent requestCompleted(Me, Nothing)
IsBusy = False
Exit Sub
End If
If retryAttempts.counter >= numberOfRetryAttempts Then 'ToDo a retry number of attempts before quits
Threading.Thread.CurrentThread.CurrentUICulture = Globalization.CultureInfo.GetCultureInfo(state.currentLang)
Dim MsgBox As messageBoxForm
MsgBox = New messageBoxForm(retryAttempts.errorMessage & ". " & My.Resources.strings.tryAgain & " ?", My.Resources.strings.question, MessageBoxButtons.YesNo, MessageBoxIcon.Question)
If MsgBox.ShowDialog() = DialogResult.Yes Then
Dim retry As _retry_attempts
With retry
.counter = 0
.previousPattern = -1
.pattern = 0
.errorMessage = ""
End With
retryAttempts = retry
startSendQueue()
Else
RestartQueueTimer.Stop()
queue = New List(Of _queue_data_struct)
RaiseEvent requestCompleted(Me, Nothing)
IsBusy = False
Exit Sub
End If
Exit Sub
ElseIf Not sendToQueue And QueuesToSend(queue) > 0 Then
startSendQueue()
End If
End Sub
Private Sub startSendQueue()
sendToQueue = True
While QueuesToSend(queue) > 0
For shtIndex = 0 To threadCount
For i = 0 To queue.Count - 1
If Not bwDataRequest(shtIndex).IsBusy Then
SyncLock queueLock
If queue.ElementAt(i).status.Equals(0) Then
Dim data As New _queue_data_struct
data.vars = queue.ElementAt(i).vars
data.status = 1
data.misc = queue.ElementAt(i).misc
data.filenameOrSavePath = queue.ElementAt(i).filenameOrSavePath
queue(i) = data
queueBWorker(shtIndex) = i
dataStatistics(shtIndex) = (New _data_statistics)
bwDataRequest(shtIndex).RunWorkerAsync(queue(i))
Threading.Thread.Sleep(50)
End If
End SyncLock
End If
Next i
Next shtIndex
End While
sendToQueue = False
End Sub
Public Function QueuesToSend(queue As List(Of _queue_data_struct)) As Integer
Dim counter As Integer = 0
For i = 0 To queue.Count - 1
If queue(i).status.Equals(0) Then
counter += 1
End If
Next i
Return counter
End Function
Public Function QueuesToComplete(queue As List(Of _queue_data_struct)) As Integer
Dim counter As Integer = 0
For i = 0 To queue.Count - 1
If queue(i).status.Equals(1) Then
counter += 1
End If
Next i
Return counter
End Function
Public Function QueuesMultiHash(queue As List(Of _queue_data_struct)) As Integer
Dim counter As Integer = 0
For i = 0 To queue.Count - 1
If queue(i).status.Equals(1) Then
counter += i
End If
Next i
Return counter
End Function
Public Function IsBase64String(ByVal s As String) As Boolean
s = s.Trim()
Return (s.Length Mod 4 = 0) AndAlso Regex.IsMatch(s, "^[a-zA-Z0-9\+/]*={0,3}$", RegexOptions.None)
End Function
'+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Public Function ConvertDataToArray(key As String, fields As String(), response As String) As Dictionary(Of String, List(Of String))
If GetMessage(response).Equals("1001") Then
Threading.Thread.CurrentThread.CurrentUICulture = Globalization.CultureInfo.GetCultureInfo(state.currentLang)
errorMessage = "{'error':true,'message':'" & My.Resources.strings.errorNoRecordsFound & "'}"
Return Nothing
End If
Try
Dim jsonResult = JsonConvert.DeserializeObject(Of Dictionary(Of String, Object))(response)
If jsonResult.ContainsKey(key) Then
If Not jsonResult.Item(key).item(0).Count.Equals(fields.Length) Then
Threading.Thread.CurrentThread.CurrentUICulture = Globalization.CultureInfo.GetCultureInfo(state.currentLang)
errorMessage = "{'error':true,'message':'" & My.Resources.strings.JsonFieldsMismatch & ". table(" & key & "'}"
Return Nothing
Else
Dim results = New Dictionary(Of String, List(Of String))
For k = 0 To fields.Length - 1
Dim fieldValues As List(Of String) = New List(Of String)
For i = 0 To jsonResult.Item(key).Count - 1
fieldValues.Add(jsonResult.Item(key).item(i).item(k).ToString)
Next i
results.Add(fields(k), fieldValues)
Next k
Return results
End If
Else
Threading.Thread.CurrentThread.CurrentUICulture = Globalization.CultureInfo.GetCultureInfo(state.currentLang)
errorMessage = "{'error':true,'message':'" & My.Resources.strings.JsonkeyNotFound & " (" & key & "'}"
Return Nothing
End If
Catch ex As Exception
errorMessage = "{'error':true,'message':'" & ex.ToString & "'}"
errorMessage = ex.ToString
Return Nothing
End Try
End Function
End Class
AeonLabs。environment是一个具有集合或字段和属性的类。
下面这个是POST请求:
Imports System.ComponentModel
Imports System.IO
Imports System.Net
Imports System.Text
Imports System.Web
Imports System.Web.Script.Serialization
Imports System.Windows.Forms
Imports AeonLabs.Environment
Imports AeonLabs.Security
Public Class HttpDataPostData
Inherits HttpDataCore
Public Event updateProgress(sender As Object, misc As Dictionary(Of String, String))
Public Event dataArrived(sender As Object, requestData As String, misc As Dictionary(Of String, String))
Public Sub New(ByVal Optional _state As environmentVarsCore = Nothing, ByVal Optional _url As String = "")
MyBase.New(_state, _url)
End Sub
Public Sub initialize(ByVal Optional _threadCount As Integer = 0)
If Not _threadCount.Equals(0) Then
threadCount = _threadCount
End If
ReDim bwDataRequest(threadCount)
ReDim queueBWorker(threadCount)
For shtIndex = 0 To threadCount
dataStatistics.Add(New _data_statistics)
bwDataRequest(shtIndex) = New System.ComponentModel.BackgroundWorker
bwDataRequest(shtIndex).WorkerReportsProgress = True
bwDataRequest(shtIndex).WorkerSupportsCancellation = True
AddHandler bwDataRequest(shtIndex).DoWork, AddressOf bwDataRequest_DoWork
AddHandler bwDataRequest(shtIndex).RunWorkerCompleted, AddressOf bwDataRequest_RunWorkerCompleted
Next shtIndex
Dim retry As _retry_attempts
With retry
.counter = 0
.previousPattern = -1
.pattern = 0
.errorMessage = ""
End With
retryAttempts = retry
End Sub
Private Sub bwDataRequest_DoWork(ByVal sender As System.Object, ByVal e As System.ComponentModel.DoWorkEventArgs)
' Find out the Index of the bWorker that called this DoWork (could be cleaner, I know)
Dim Y As Integer
Dim Index As Integer = Nothing
For Y = 0 To UBound(bwDataRequest)
If sender.Equals(bwDataRequest(Y)) Then
Index = Y
Exit For
End If
Next Y
Dim queue As _queue_data_struct
queue = e.Argument
Dim vars As New Dictionary(Of String, String)
vars = queue.vars
'TODO translation need to be local
If Not System.Net.NetworkInformation.NetworkInterface.GetIsNetworkAvailable() Then
Threading.Thread.CurrentThread.CurrentUICulture = System.Globalization.CultureInfo.GetCultureInfo(state.currentLang)
e.Result = "{'error':true,'message':'" & My.Resources.strings.errorNoNetwork & "'}"
Exit Sub
End If
If vars Is Nothing Then
e.Result = "{'error':true,'message':'missconfiguration vars'}"
Exit Sub
End If
If Not vars.ContainsKey("id") Then
vars.Add("id", state.userId)
End If
If Not vars.ContainsKey("pid") Then
Dim appId As New FingerPrint
vars.Add("pid", appId.Value)
End If
If Not vars.ContainsKey("language") Then
vars.Add("language", state.currentLang)
End If
If Not vars.ContainsKey("origin") Then
vars.Add("origin", state.softwareAccessMode)
End If
Dim serializer As New JavaScriptSerializer()
Dim json As String = serializer.Serialize(vars)
Dim encryption As New AesCipher(state)
Dim encrypted As String = HttpUtility.UrlEncode(encryption.encrypt(json))
Dim PostData = "origin=" & state.softwareAccessMode & "&data=" & encrypted
Dim request As WebRequest = WebRequest.Create(url)
Dim responseFromServer As String = ""
Dim decrypted As String = ""
request.Method = "POST"
Dim byteArray As Byte() = Encoding.UTF8.GetBytes(PostData)
request.ContentType = "application/x-www-form-urlencoded"
request.Headers.Add("Authorization", state.ApiHttpHeaderToken & "-" & state.softwareAccessMode)
request.ContentLength = byteArray.Length
Try
Dim dataStream As Stream = request.GetRequestStream()
dataStream.Write(byteArray, 0, byteArray.Length)
dataStream.Close()
Dim response As HttpWebResponse = CType(request.GetResponse(), HttpWebResponse)
dataStream = response.GetResponseStream()
Dim reader As New StreamReader(dataStream)
responseFromServer = reader.ReadToEnd()
reader.Close()
dataStream.Close()
response.Close()
If response.StatusCode = HttpStatusCode.Accepted Or response.StatusCode = 200 Then
If IsBase64String(responseFromServer) And Not responseFromServer.Equals("") Then
decrypted = encryption.decrypt((responseFromServer)).Replace("\'", "'")
Else
Threading.Thread.CurrentThread.CurrentUICulture = System.Globalization.CultureInfo.GetCultureInfo(state.currentLang)
decrypted = "{'error':true,'encrypted':false,'message':'" & My.Resources.strings.contactingCommServer & " |" & responseFromServer & "|'}"
End If
Else
Threading.Thread.CurrentThread.CurrentUICulture = System.Globalization.CultureInfo.GetCultureInfo(state.currentLang)
decrypted = "{'error':true,'message':'" & My.Resources.strings.contactingCommServer & " (" & response.StatusCode & ")', 'statuscode':'" & response.StatusCode & "'}"
End If
Catch ex As Exception
Threading.Thread.CurrentThread.CurrentUICulture = System.Globalization.CultureInfo.GetCultureInfo(state.currentLang)
decrypted = "{'error':true,'message':'" & My.Resources.strings.contactingCommServer & " (" & ex.Message.ToString.Replace("'", "\'") & ")'}"
End Try
e.Result = decrypted.Replace("\'", "'")
End Sub
Private Sub bwDataRequest_RunWorkerCompleted(ByVal sender As Object, ByVal e As System.ComponentModel.RunWorkerCompletedEventArgs)
' Find out the Index of the bWorker that called this DoWork (could be cleaner, I know)
Dim Y As Integer
Dim Index As Integer = Nothing
Dim data As New _queue_data_struct
For Y = 0 To UBound(bwDataRequest)
If sender.Equals(bwDataRequest(Y)) Then
Index = Y
Exit For
End If
Next Y
If IsResponseOk(e.Result, "statuscode") Then
data = New _queue_data_struct
data = queue(queueBWorker(Index))
data.status = 0 're queue the file
SyncLock queueLock
queue(queueBWorker(Index)) = data
End SyncLock
Dim errorMsg As String = GetMessage(e.Result)
Dim retry As _retry_attempts
With retry
.counter = retryAttempts.counter
.previousPattern = retryAttempts.previousPattern
.pattern = retryAttempts.pattern
.errorMessage = retryAttempts.errorMessage
End With
retry.errorMessage = If(retryAttempts.errorMessage.IndexOf(errorMsg) > -1, retryAttempts.errorMessage, retryAttempts.errorMessage & System.Environment.NewLine & errorMsg)
retry.pattern = QueuesMultiHash(queue)
If retry.previousPattern.Equals(retry.pattern) Then
retry.counter += 1
Else
retry.counter = 1
retry.previousPattern = retryAttempts.pattern
End If
retryAttempts = retry
Exit Sub
End If
data = New _queue_data_struct
data = queue(queueBWorker(Index))
data.status = -1 'completed sucessfully status
SyncLock queueLock
queue(queueBWorker(Index)) = data
End SyncLock
loadingCounter += 1
CompletionPercentage = (loadingCounter / queue.Count) * 100
statusMessage = "Loading data from the cloud..."
RaiseEvent updateProgress(Me, queue(queueBWorker(Index)).misc)
RaiseEvent dataArrived(Me, e.Result, queue(queueBWorker(Index)).misc)
End Sub
End Class
Aoenlabs。Security是用于发送使用标准加密算法加密的POST数据的类。
其他回答
这里有一些非常好的答案。让我发布一种不同的方法来设置你的头部与WebClient()。我还将向您展示如何设置API键。
var client = new WebClient();
string credentials = Convert.ToBase64String(Encoding.ASCII.GetBytes(userName + ":" + passWord));
client.Headers[HttpRequestHeader.Authorization] = $"Basic {credentials}";
//If you have your data stored in an object serialize it into json to pass to the webclient with Newtonsoft's JsonConvert
var encodedJson = JsonConvert.SerializeObject(newAccount);
client.Headers.Add($"x-api-key:{ApiKey}");
client.Headers.Add("Content-Type:application/json");
try
{
var response = client.UploadString($"{apiurl}", encodedJson);
//if you have a model to deserialize the json into Newtonsoft will help bind the data to the model, this is an extremely useful trick for GET calls when you have a lot of data, you can strongly type a model and dump it into an instance of that class.
Response response1 = JsonConvert.DeserializeObject<Response>(response);
这个解决方案只使用标准的. net调用。
测试:
在企业WPF应用程序中使用。使用async/await来避免阻塞UI。 兼容。net 4.5+。 在没有参数的情况下进行测试(在幕后需要一个“GET”)。 使用参数进行测试(需要幕后的“POST”)。 使用标准的网页(如谷歌)进行测试。 使用内部基于java的web服务进行测试。
参考:
// Add a Reference to the assembly System.Web
代码:
using System;
using System.Collections.Generic;
using System.Collections.Specialized;
using System.Net;
using System.Net.Http;
using System.Threading.Tasks;
using System.Web;
private async Task<WebResponse> CallUri(string url, TimeSpan timeout)
{
var uri = new Uri(url);
NameValueCollection rawParameters = HttpUtility.ParseQueryString(uri.Query);
var parameters = new Dictionary<string, string>();
foreach (string p in rawParameters.Keys)
{
parameters[p] = rawParameters[p];
}
var client = new HttpClient { Timeout = timeout };
HttpResponseMessage response;
if (parameters.Count == 0)
{
response = await client.GetAsync(url);
}
else
{
var content = new FormUrlEncodedContent(parameters);
string urlMinusParameters = uri.OriginalString.Split('?')[0]; // Parameters always follow the '?' symbol.
response = await client.PostAsync(urlMinusParameters, content);
}
var responseString = await response.Content.ReadAsStringAsync();
return new WebResponse(response.StatusCode, responseString);
}
private class WebResponse
{
public WebResponse(HttpStatusCode httpStatusCode, string response)
{
this.HttpStatusCode = httpStatusCode;
this.Response = response;
}
public HttpStatusCode HttpStatusCode { get; }
public string Response { get; }
}
不带参数调用(在幕后使用“GET”):
var timeout = TimeSpan.FromSeconds(300);
WebResponse response = await this.CallUri("http://www.google.com/", timeout);
if (response.HttpStatusCode == HttpStatusCode.OK)
{
Console.Write(response.Response); // Print HTML.
}
使用参数调用(在幕后使用“POST”):
var timeout = TimeSpan.FromSeconds(300);
WebResponse response = await this.CallUri("http://example.com/path/to/page?name=ferret&color=purple", timeout);
if (response.HttpStatusCode == HttpStatusCode.OK)
{
Console.Write(response.Response); // Print HTML.
}
简单的GET请求
using System.Net;
...
using (var wb = new WebClient())
{
var response = wb.DownloadString(url);
}
简单的POST请求
using System.Net;
using System.Collections.Specialized;
...
using (var wb = new WebClient())
{
var data = new NameValueCollection();
data["username"] = "myUser";
data["password"] = "myPassword";
var response = wb.UploadValues(url, "POST", data);
string responseInString = Encoding.UTF8.GetString(response);
}
为什么这不是完全无关紧要的?执行请求并不是处理结果。而且似乎还涉及到一些。net Bug——参见HttpClient中的Bug。GetAsync应该抛出WebException,而不是TaskCanceledException
我最终得到了这样的代码:
static async Task<(bool Success, WebExceptionStatus WebExceptionStatus, HttpStatusCode? HttpStatusCode, string ResponseAsString)> HttpRequestAsync(HttpClient httpClient, string url, string postBuffer = null, CancellationTokenSource cts = null) {
try {
HttpResponseMessage resp = null;
if (postBuffer is null) {
resp = cts is null ? await httpClient.GetAsync(url) : await httpClient.GetAsync(url, cts.Token);
} else {
using (var httpContent = new StringContent(postBuffer)) {
resp = cts is null ? await httpClient.PostAsync(url, httpContent) : await httpClient.PostAsync(url, httpContent, cts.Token);
}
}
var respString = await resp.Content.ReadAsStringAsync();
return (resp.IsSuccessStatusCode, WebExceptionStatus.Success, resp.StatusCode, respString);
} catch (WebException ex) {
WebExceptionStatus status = ex.Status;
if (status == WebExceptionStatus.ProtocolError) {
// Get HttpWebResponse so that you can check the HTTP status code.
using (HttpWebResponse httpResponse = (HttpWebResponse)ex.Response) {
return (false, status, httpResponse.StatusCode, httpResponse.StatusDescription);
}
} else {
return (false, status, null, ex.ToString());
}
// https://devblogs.microsoft.com/dotnet/net-5-new-networking-improvements/
} catch (TaskCanceledException ex) when (ex.InnerException is TimeoutException) {
return (false, ex.ToString(), null, WebExceptionStatus.Timeout);
} catch (TaskCanceledException ex) {
return (false, ex.ToString(), null, WebExceptionStatus.RequestCanceled);
} catch (Exception ex) {
return (false, WebExceptionStatus.UnknownError, null, ex.ToString());
}
}
这将根据postBuffer是否为空来执行GET或POST操作。
如果Success为true,响应将在ResponseAsString中。
如果Success为false,你可以检查WebExceptionStatus, HttpStatusCode和ResponseAsString,看看哪里出了问题。
MSDN有一个样本。
using System;
using System.IO;
using System.Net;
using System.Text;
namespace Examples.System.Net
{
public class WebRequestPostExample
{
public static void Main()
{
// Create a request using a URL that can receive a post.
WebRequest request = WebRequest.Create("http://www.contoso.com/PostAccepter.aspx");
// Set the Method property of the request to POST.
request.Method = "POST";
// Create POST data and convert it to a byte array.
string postData = "This is a test that posts this string to a Web server.";
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
// Set the ContentType property of the WebRequest.
request.ContentType = "application/x-www-form-urlencoded";
// Set the ContentLength property of the WebRequest.
request.ContentLength = byteArray.Length;
// Get the request stream.
Stream dataStream = request.GetRequestStream();
// Write the data to the request stream.
dataStream.Write(byteArray, 0, byteArray.Length);
// Close the Stream object.
dataStream.Close();
// Get the response.
WebResponse response = request.GetResponse();
// Display the status.
Console.WriteLine(((HttpWebResponse)response).StatusDescription);
// Get the stream containing content returned by the server.
dataStream = response.GetResponseStream();
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader(dataStream);
// Read the content.
string responseFromServer = reader.ReadToEnd();
// Display the content.
Console.WriteLine(responseFromServer);
// Clean up the streams.
reader.Close();
dataStream.Close();
response.Close();
}
}
}
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