将数组作为 Httpclient multipart/form-data 发布到 api

Question

我有一个端点请求我发送一个数组作为我的身体数据的一部分，下面是我使用多部分表单数据的代码。如何将阵列发送到我的端点。

var file = _mediaFile.Path;
if (string.IsNullOrEmpty(file) == false)
{
var upfilebytes = System.IO.File.ReadAllBytes(file);
MultipartFormDataContent content = new MultipartFormDataContent();
ByteArrayContent baContent = new ByteArrayContent(upfilebytes);
var name = System.IO.Path.GetFileName(file);
baContent.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue("image/" + System.IO.Path.GetExtension(name).Remove(0, 1));
baContent.Headers.ContentDisposition = new System.Net.Http.Headers.ContentDispositionHeaderValue("form-data")
{
Name = "Image",
FileName = name,
};
var categorynew = new List<string>();
categorynew.Add(((Categorypicker.SelectedItem as CategoriesModel).category));
var categoryArray = categorynew.ToArray();
content.Add(baContent, "Image", name);
content.Add(new StringContent(DealerAddr.Text), "DealersAddress");
content.Add(new StringContent(itemName.Text), "ItemName");
content.Add(new StringContent(itemDescription.Text), "ItemDescription");
content.Add(new StringContent(itemPrice.Text), "PreferredPrice");
content.Add(new StringContent(DealerPhone.Text), "DealerPhone");
content.Add(new StringContent(DealerCity.Text), "City");
content.Add(new StringContent(StoreUrl.Text), "SellerWeblink");
content.Add(new StringContent (categorynew,"Category_Name");
content.Add(new StringContent((Categorypicker.SelectedItem as CategoriesModel).category), "Category_Name");
var response = await client.PostAsync(CreateItem, content);
if (response.IsSuccessStatusCode) 
{
}
}

Answer 1

好的，我后来通过将数组转换回 json 来解决这个问题，然后再将其添加到我的内容中。

var categorynew = new List<string>();
categorynew.Add(((Categorypicker.SelectedItem as CategoriesModel).category));
var categoryArray = categorynew.ToArray();
var jsoncategoryArray = JsonConvert.SerializeObject(categoryArray);
content.Add(baContent, "Image", name);
content.Add(new StringContent(DealerAddr.Text), "DealersAddress");
content.Add(new StringContent(itemName.Text), "ItemName");
content.Add(new StringContent(itemDescription.Text), "ItemDescription");
content.Add(new StringContent(itemPrice.Text), "PreferredPrice");
content.Add(new StringContent(DealerPhone.Text), "DealerPhone");
content.Add(new StringContent(DealerCity.Text), "City");
content.Add(new StringContent(StoreUrl.Text), "SellerWeblink");
content.Add(new StringContent(jsoncategoryArray),"category");

Answer 2

对我来说，有一个更好的解决方案，不需要任何数据内容操作， 假设我们正在等待名为"类别"的参数中的数组：

foreach(var cat in categories)
mfd.Add(new StringContent(arg, Encoding.UTF8), "Categories[]");