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向Silverlight HTTP Post Async添加数据

http-post silverlight-3.0 silverlight

3

Toran Billups · 技术社区 · 15 年前

我试图使用Silverlight3.0中的一个简单的HTTP帖子发送一些数据,但出于某种原因,我似乎找不到一个好的例子来说明如何做到这一点。

到目前为止,这是可行的,但是我如何在请求的同时发送一些数据呢?

Public Sub SubmitMessage()
    request = WebRequestCreator.ClientHttp.Create(New System.Uri("http://localhost:27856/Home.aspx/PostUpdate/"))
    request.Method = "POST"

    Dim result As IAsyncResult = request.BeginGetResponse(New AsyncCallback(AddressOf UpdateDone), Nothing)
End Sub

Public Sub UpdateDone(ByVal ar As IAsyncResult)
    Dim response As HttpWebResponse = request.EndGetResponse(ar)

    Using reader As StreamReader = New StreamReader(response.GetResponseStream())
        Dim valid As String = reader.ReadToEnd()
    End Using
End Sub

2 回复 | 直到 11 年前

1

AnthonyWJones 15 年前

你需要 BeginGetRequestStream 方法,然后获取响应(注意vb.net不是我的主要语言)。

Public Sub SubmitMessage()
    request = WebRequestCreator.ClientHttp.Create(New System.Uri("http://localhost:27856/Home.aspx/PostUpdate/"))
    request.Method = "POST"

    request.BeginGetRequestStream(New AsyncCallback(AddressOf SendData), Nothing)
End Sub

Public Sub SendData(ByVal ar As IAsyncResult)
    Dim stream as Stream = state.Request.EndGetRequestStream(ar)
    '' # Pump your data as bytes into the stream.
    stream.Close()
    request.BeingGetResponse(New AsyncCallback(AddressOf UpdateDone), Nothing)
End Sub

Public Sub UpdateDone(ByVal ar As IAsyncResult)
    Dim response As HttpWebResponse = request.EndGetResponse(ar)

    Using reader As StreamReader = New StreamReader(response.GetResponseStream())
        Dim valid As String = reader.ReadToEnd()
    End Using
End Sub

从您的回答来看,似乎正在发布HTML表单数据。以下是创建实体主体的正确方法(C抱歉):-

    public static string GetUrlEncodedData(Dictionary<string, string> data)
    {
        var sb = new StringBuilder();
        foreach (var kvp in data)
        {
            if (sb.Length > 0) sb.Append("&");
            sb.Append(kvp.Key);
            sb.Append("=");
            sb.Append(Uri.EscapeDataString(kvp.Value));
        }
        return sb.ToString();
    }

特别注意 Uri.EscapeDataString ,这是对此内容类型的数据值进行编码的正确方法。它假定服务器需要UTF-8字符编码。

当将结果转换为准备发布的字节数组时,您只需要使用ASCII编码,因为返回的字符串将只包含ASCII范围内的字符。

2

1

Community CDub 8 年前

最终的解决方案如下所示。感谢@ AnthonyWJones 因为他的快速回答让我朝着正确的方向前进!

Public Sub SubmitMessage()
    Dim request As HttpWebRequest = WebRequestCreator.ClientHttp.Create(New System.Uri("http://localhost:27856/Home.aspx/PostUpdate/"))
    request.Method = "POST"
    request.ContentType = "application/x-www-form-urlencoded"

    request.BeginGetRequestStream(New AsyncCallback(AddressOf SendStatusUpdate), request)
End Sub

Public Sub SendStatusUpdate(ByVal ar As IAsyncResult)
    Dim request As HttpWebRequest = DirectCast(ar.AsyncState, HttpWebRequest)

    Dim stream As Stream = request.EndGetRequestStream(ar)

    Dim data As New System.Text.UTF8Encoding
    Dim byteArray As Byte() = data.GetBytes("status=test")

    stream.Write(byteArray, 0, byteArray.Length)
    stream.Close()
    stream.Dispose()

    request.BeginGetResponse(New AsyncCallback(AddressOf StatusUpdateCompleted), request)
End Sub

Public Sub StatusUpdateCompleted(ByVal ar As IAsyncResult)
    Dim request As HttpWebRequest = DirectCast(ar.AsyncState, HttpWebRequest)

    Dim response As HttpWebResponse = request.EndGetResponse(ar)

    Using reader As StreamReader = New StreamReader(response.GetResponseStream())
        Dim valid As String = reader.ReadToEnd()
    End Using
End Sub