从ASP.NET网站使用c＃从默认的电子邮件客户端（例如Outlook，..）发送电子邮件

Question

I'm working on my very first project, and I need to add a function as the button_click event. Function should open a "send new e-mail" form of the default email client, empty, without any destination,subject or body just with an attached file.

I went through many similar tutorial on the stackoverflow and codeproject but couldn't solve it. I found similar functions which send a message from code, but not just open an empty e-mail form and attach the required file. But couldn't modify successfully.

I'm sure there are people looking for this kind of solution as well.

what I tried so far is :

protected void btnSend_Click(object sender, EventArgs e)
{
    string value;
    value = lstpdfList.SelectedItem.Text;
    string file = "W:/" + value + ".pdf";

    MailMessage message = new MailMessage();
    Attachment data = new Attachment(file, MediaTypeNames.Application.Octet);
    ContentDisposition disposition = data.ContentDisposition;
    disposition.CreationDate = System.IO.File.GetCreationTime(file);
    disposition.ModificationDate = System.IO.File.GetLastWriteTime(file);
    disposition.ReadDate = System.IO.File.GetLastWriteTime(file);
    message.Attachments.Add(data);
}

Answer 1

You can't attach a file from ASP.net to outlook, it's a security issue.

If you have access to the Exchange Web Services you can interact directly with Exchange to send an e-mail from that users account with attachments etc.

You may have to delegate access to the user account used to execute the ASP.NET request to successfully be able to interact with the Exchange Server Services, you could use ASP.net impersonate as well.

Check out the documentation at:

http://msdn.microsoft.com/en-us/library/exchange/bb409286(v=exchg.140).aspx

Answer 2

You can't automate Outlook on the client-side from a web application. And you shouldn't invoke Outlook on the server.

What you can do however is to send an email from the web server, without involving Outlook.

To do this, just follow the example on MSDN for SmtpClient.Send() .

There's also an example of programmatically creating a MailMessage with attachments here .

public static void CreateTestMessage2(string server)
{
    string to = "jane@contoso.com";
    string from = "ben@contoso.com";
    MailMessage message = new MailMessage(from, to);
    message.Subject = "Using the new SMTP client.";
    message.Body = @"Using this new feature, you can send an e-mail message from an application very easily.";
    SmtpClient client = new SmtpClient(server);
    // Credentials are necessary if the server requires the client  
    // to authenticate before it will send e-mail on the client's behalf.
    client.UseDefaultCredentials = true;

    try 
    {
        client.Send(message);
    }  
    catch (Exception ex) 
    {
        Console.WriteLine("Exception caught in CreateTestMessage2(): {0}", ex.ToString() );           
    }              
}