can eml directly open with outlook, instead eml file will download then click it to open in outlook? - asp.net-mvc

Question

I have an asp.net MVC application, below code works file.
But the code is that, When navigate to Email action in browser, an EML file is download, then when we click on that file, the file will open with outlook.
Can it be possible, when action calls, then EML file will directly open with outlook, instead of download and then click to open??
Code
public async Task<FileStreamResult> Email()
{
string dummyEmail = "test#localhost.com";
var mailMessage = new MailMessage();
mailMessage.From = new MailAddress(dummyEmail);
mailMessage.To.Add("dejan.caric#gmail.com");
mailMessage.Subject = "Test subject";
mailMessage.Body = "Test body";
// mark as draft
mailMessage.Headers.Add("X-Unsent", "1");
// download image and save it as attachment
using (var httpClient = new HttpClient())
{
var imageStream = await httpClient.GetStreamAsync(new Uri("http://dcaric.com/favicon.ico"));
mailMessage.Attachments.Add(new Attachment(imageStream, "favicon.ico"));
}
var stream = new MemoryStream();
ToEmlStream(mailMessage, stream, dummyEmail);
stream.Position = 0;
return File(stream, "message/rfc822", "test_email.eml");
}
private void ToEmlStream(MailMessage msg, Stream str, string dummyEmail)
{
using (var client = new SmtpClient())
{
var id = Guid.NewGuid();
var tempFolder = Path.Combine(Path.GetTempPath(), Assembly.GetExecutingAssembly().GetName().Name);
tempFolder = Path.Combine(tempFolder, "MailMessageToEMLTemp");
// create a temp folder to hold just this .eml file so that we can find it easily.
tempFolder = Path.Combine(tempFolder, id.ToString());
if (!Directory.Exists(tempFolder))
{
Directory.CreateDirectory(tempFolder);
}
client.UseDefaultCredentials = true;
client.DeliveryMethod = SmtpDeliveryMethod.SpecifiedPickupDirectory;
client.PickupDirectoryLocation = tempFolder;
client.Send(msg);
// tempFolder should contain 1 eml file
var filePath = Directory.GetFiles(tempFolder).Single();
// create new file and remove all lines that start with 'X-Sender:' or 'From:'
string newFile = Path.Combine(tempFolder, "modified.eml");
using (var sr = new StreamReader(filePath))
{
using (var sw = new StreamWriter(newFile))
{
string line;
while ((line = sr.ReadLine()) != null)
{
if (!line.StartsWith("X-Sender:") &&
!line.StartsWith("From:") &&
// dummy email which is used if receiver address is empty
!line.StartsWith("X-Receiver: " + dummyEmail) &&
// dummy email which is used if receiver address is empty
!line.StartsWith("To: " + dummyEmail))
{
sw.WriteLine(line);
}
}
}
}
// stream out the contents
using (var fs = new FileStream(newFile, FileMode.Open))
{
fs.CopyTo(str);
}
}
}

Answer 1

With Chrome you can make it automatically open certain files, once they are downloaded.
.EML should attempt to open in Outlook.
I am not sure about other browsers, but Chrome seemed to be the only one with this option.
It's not a pefect solution because if someone downloaded an .EML from another website in Chrome, it will open automatically aswell.
I recommend having Chrome dedicated to your Web application.

Answer 2

You sure can open local .eml file with Outlook.
But in context of web application, you must firstly download it.