Line breaks being removed from email body

Question

I'm generating a simple email using the System.Net.Mail.MailMessage class and building the body with a StringBuilder. I'm looping through a string[] and trying to append a new line each time. The problem I'm having is that I can't seem to generate a single new line each time. I can either get two or none.

What I've tried:

foreach (var message in messages)
{
    body.AppendLine(message);
}

foreach (var message in messages)
{
    body.Append(message + "\n");
}

foreach (var message in messages)
{
    body.Append(message + System.Environment.NewLine);
}

I've also tried with string.Format().

For each example above, I get the same result. No new line being generated.

When I try the following, however, I get the expected result. A new line with an empty line in between.

foreach (var message in messages)
{
    body.AppendLine(message + System.Environment.NewLine);
}

Why is it doing this and what can I do to just get a single new line each time?

Update:

So I've found that Outlook and probably Gmail (haven't tested others) are actually removing some line breaks and not others. Does anyone know why or how they determine what to remove?

Answer 1

When I checked the email in Outlook, I got a tiny info message saying "Extra line breaks in this message were removed" and the option to restore them. Gmail gave no such indication (that I found) but I must assume it removed them as well.

Interestingly enough I had line breaks elsewhere in the body that worked as expected, only the ones in the loop were deemed "extra".

I have modified my code to build the email body using html.

IsBodyHtml = true

If anyone knows of a way to prevent this, or what causes certain line breaks to be removed, please let me know.

Update:

Once I knew what I was looking for, I found this post which helps to explain things and gives some alternate solutions. I did not try any of them, as I think using html is the better solution in my case.

Answer 2

I have just ran this through LINQPad

string[] messages = new string[]{"First line in message", "Second Line in message", "Third Line in message"};

StringBuilder sbA = new StringBuilder();
StringBuilder sbB = new StringBuilder();
StringBuilder sbC = new StringBuilder();
StringBuilder sbD = new StringBuilder();

// New line for each string
foreach (var message in messages)
{
    sbA.AppendLine(message);
}

// New line for each string
foreach (var message in messages)
{
    sbB.Append(message + "\n");
}

// New line for each string
foreach (var message in messages)
{
    sbC.Append(message + System.Environment.NewLine);
}

//One Line
foreach (var message in messages)
{
    sbD.Append(message);
}


sbA.Dump();
sbB.Dump();
sbC.Dump();
sbD.Dump();

Each one performs as expected in a StringBuilder sense.

I suspect that you need to add "</br>" at the end of each AppendLine something like this (not tested):

MailMessage mail = new MailMessage(new MailAddress("someSender@email.com"), new MailAddress("someReceiver@email.com"));
string[] messages = new string[]{"First line in message", "Second Line in message", "Third Line in message"};

StringBuilder body = new StringBuilder();

body.AppendLine("<h2>My Message<h2></br>" );

foreach (var message in messages)
{
    body.AppendLine(message + "</br>");
}

mail.Body = body.ToString();

mail.Dump();

Answer 3

Gmail will remove explicit line breaks. This code works for me when sending to Gmail, as well as Outlook with proper line breaks intact. I am completely unable to replicate your issue without seeing what your messages[] array looks like. It may be possible that some formatting could be viewed as line breaks causing all to be stripped out? I have tampered with my example strings and I cannot get Outlook nor Gmail to strip the line breaks on me.

    private void SendMessage()
    {
        try
        {
            StringBuilder body = new StringBuilder();
            string[] messages = { "test with    a tab in it", "    test with     spaces", " \r\nTab, then line break", "\n\n\n\n\n\nlots of returns...", "                test spaces" };

            foreach (var msg in messages)
            {
                body.AppendLine(msg);
                //body.AppendLine(string.Empty);
            }


            using (MailMessage message = new MailMessage())
            {
                message.From = new MailAddress("you@test.com", "Your Display Name");
                message.ReplyToList.Add("reply-email@test.com");
                message.To.Add("to@test.com");
                message.Subject = "Test Line Break Message";
                message.IsBodyHtml = false;
                message.Priority = MailPriority.Normal;
                message.BodyEncoding = System.Text.Encoding.UTF8;
                message.Body = body.ToString();

                using (SmtpClient smtpClient = new SmtpClient())
                {
                    smtpClient.Host = "127.0.0.1";
                    smtpClient.Send(message);
                }
            }
        }
        catch (Exception e)
        {
            MessageBox.Show(e.Message);
        }
    }

I am going to assume somewhere in your code that builds or retrieves the messages array, something is happening to cause this issue. I would believe it to be fixable, but not without seeing how that part is coded.