Microsoft.XMLHTTP 代码转换为 C# 时出现内部服务器错误

Question

我继承了一些将一些数据上传到网站的 VB6 代码。我正在尝试将其转换为 C#。我最初尝试使用 WebRequest 对象，但做了更多研究后，我尝试了 WebClient。两个好像都有问题

这是我继承的代码：

' The object that will make the call to the WS
Set oXMLHTTP = CreateObject("Microsoft.XMLHTTP")

' Tell the name of the subroutine that will handle the response
'oXMLHTTP.onreadystatechange = HandleStateChange
' Initializes the request (the last parameter, False in this case, tells if the call is asynchronous or not
oXMLHTTP.Open "POST", "https://path.to.webpage/Update.asmx/UpdatePage", False
' This is the content type that is expected by the WS using the HTTP POST protocol
oXMLHTTP.setRequestHeader "Content-Type", "application/x-www-form-urlencoded"

'Now we send the request to the WS
oXMLHTTP.send "userName=user&password=password&html=" & ThisMessage

ThisMessage其实是动态创建了一个字符串html.

这是 vb6 代码的 c# 翻译：

public static void PostHTML(string uri)
    {
        NetworkCredential credential = new NetworkCredential("user", "password");

        WebClient request = new WebClient();
        request.UseDefaultCredentials = false;
        request.Credentials = credential;

        request.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";

        string postString = GetWebTemplate();
        //byte[] byteArray = Encoding.UTF8.GetBytes(postData);

        var response = request.UploadString(uri,"POST", postString);

        Debug.WriteLine(response);
        request.Dispose();
    }

这是纯 "test" 代码。 uri 是 "https://path.to.webpage/Update.asmx/UpdatePage"，虽然 postString 与 thisMessage 不同，但它是一个有效的 html 页面。我试过 request.UploadString() 和 request.UploadData() （使用已被注释掉的 byteArray）。我也尝试过更改编码。

我遇到的问题是：

Exception thrown: 'System.Net.WebException' in System.dll An unhandled exception of type 'System.Net.WebException' occurred in System.dll Additional information: The remote server returned an error: (500) Internal Server Error.

我不确定为什么会收到内部服务器错误，因为 VB6 代码仍然很高兴运行没有错误！

有什么建议吗？

Answer 1

根据@pcdev 的建议，这是最终有效的代码：

    public static void PostHTML(string uri)
    {
        WebClient request = new WebClient();
        request.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";
        string postString = "userName=user&password=password&html=" + GetWebTemplate();
        var response = request.UploadString(uri,"POST", postString);
        Debug.WriteLine(response);
        request.Dispose();
    }

Microsoft.XMLHTTP 代码转换为 C# 时出现内部服务器错误

Internal Server Error with Microsoft.XMLHTTP code converted to C#

c#

vb6

webclient