如何将 IFormFile 转换为 C# 中的 byte[]？

Question

I receive IFormFile and I would like to convert it to byte[] , my code looks like this:

private ProductDto GenerateData(Request product, IFormFile file)
{
    if (file != null)
    { 
        using (var item = new MemoryStream())
        {
            file.CopyTo(item);
            item.ToArray();
        }
    }

    return new ProductDto
    {
        product_resp = JsonConvert.SerializeObject(product).ToString(),
        file_data = item; // I need here byte [] 
    };
}

I've tried something but I'm not even sure if I can convert IFormFile to byte[] on way I tried, not sure if it's right approach.

Anyway, thanks for any help.

Answer 1

I have an extension for it:

public static byte[] ToByteArray(this Stream input)
{
        byte[] buffer = new byte[16 * 1024];
        using (var ms = new MemoryStream())
        {
            int read;
            while ((read = input.Read(buffer, 0, buffer.Length)) > 0)
            {
                ms.Write(buffer, 0, read);
            }
            return ms.ToArray();
        }
}

then

  if (file != null)
  { 
        using (var stream = file.OpenReadStream())
        {
            return new ProductDto
            {
                product_resp = JsonConvert.SerializeObject(product).ToString(),
                file_data = stream.ToByteArray()
            };
        }
    }

Answer 2

1. You seem to be sending back the memorystream instead of a byte array.
2. stream.ToArray() returns a byte array you can use

So, your code should be

private ProductDto GenerateData(Request product, IFormFile file)
{
    byte[] fileByteArray;    //1st change here
    if (file != null)
    { 
        using (var item = new MemoryStream())
        {
            file.CopyTo(item);
            fileByteArray = item.ToArray(); //2nd change here
        }
    }

    return new ProductDto
    {
        product_resp = JsonConvert.SerializeObject(product).ToString(),
        file_data = fileByteArray; // 3rd change here
    };
}