15

我有这个代码示例作为另一个问题的答案发布(使用 C# 通过 HTTP POST 发送文件)。它工作正常,除了一个问题。它用双引号包围 HTTP 标头中的边界:

多部分/表单数据;边界="04982073-787d-414b-a0d2-8e8a1137e145"

这使我试图调用的网络服务窒息。浏览器没有那些双引号。我需要一些方法来告诉 .NET 将它们关闭。

private System.IO.Stream Upload(string actionUrl, string paramString, Stream paramFileStream, byte [] paramFileBytes)
{
    HttpContent stringContent = new StringContent(paramString);
    HttpContent fileStreamContent = new StreamContent(paramFileStream);
    HttpContent bytesContent = new ByteArrayContent(paramFileBytes);
    using (var client = new HttpClient())
    using (var formData = new MultipartFormDataContent())
    {
        formData.Add(stringContent, "param1", "param1");
        formData.Add(fileStreamContent, "file1", "file1");
        formData.Add(bytesContent, "file2", "file2");
        var response = client.PostAsync(actionUrl, formData).Result;
        if (!response.IsSuccessStatusCode)
        {
            return null;
        }
        return response.Content.ReadAsStreamAsync().Result;
    }
}
4

3 回答 3

10

您可以使用以下代码从边界中删除引号:

var boundary = formData.Headers.ContentType.Parameters.First(o => o.Name == "boundary"); 
boundary.Value = boundary.Value.Replace("\"", String.Empty);    
于 2018-01-21T20:00:43.867 回答
2

扩展dotnet 运行时 repo 中类似问题的讨论。选择不包含引号涉及两个步骤

  1. 选择你自己的非引用边界
  2. 删除自动生成的 ContentType 标头,其中一个不带引号
private System.IO.Stream Upload(string actionUrl, string paramString, Stream paramFileStream, byte [] paramFileBytes)
{
    HttpContent stringContent = new StringContent(paramString);
    HttpContent fileStreamContent = new StreamContent(paramFileStream);
    HttpContent bytesContent = new ByteArrayContent(paramFileBytes);
    //Set your own boundary, otherwise the internal boundary between multiple parts remains with quotes
    string boundaryDelimiter = String.Format("----------{0}", DateTime.Now.Ticks.ToString("x"));
    using (var client = new HttpClient())
    using (var formData = new MultipartFormDataContent(boundaryDelimiter))
    {
        formData.Add(stringContent, "param1", "param1");
        formData.Add(fileStreamContent, "file1", "file1");
        formData.Add(bytesContent, "file2", "file2");
        //remove quotes from ContentType Header
        _multiPartContent.Headers.Remove("Content-Type");
        _multiPartContent.Headers.TryAddWithoutValidation("Content-Type", "multipart/form-data; boundary=" + boundaryDelimiter);

        var response = client.PostAsync(actionUrl, formData).Result;
        if (!response.IsSuccessStatusCode)
        {
            return null;
        }
        return response.Content.ReadAsStreamAsync().Result;
    }
}
于 2020-04-24T06:54:28.460 回答
0

这是一个老问题,但我遇到了同样的问题并解决了@Luis Perez 在他的回答中指出的相同方式,但使用它的缺点是 MultipartContent 停止计算内容大小,所以这是我的解决方案:

var multipartContent = new MultipartFormDataContent();
var boundaryParameter = multipartContent.Headers.ContentType
                                        .Parameters.Single(p => p.Name == "boundary");
boundaryParameter.Value = boundaryParameter.Value.Replace("\"", "");

// --- Put the rest of content here

var size = (await multipartContent.ReadAsStreamAsync()).Length;
multipartContent.Headers.ContentLength = size;

希望这可以帮助那里的人。

于 2021-02-19T11:51:21.850 回答