Why does StringBuilder.AppendLine not add a new line with some strings?

Question

I\'m trying to use stringbuilder to create a body of string to be used in a text (not HTML) email. However some lines (where i include dynamic data, a new line is not added,

Answer 1

I know the question is old and has been marked as answered, but I thought I'd add this here in case anyone else comes across this as it's the first hit on Google for StringBuilder.AppendLine() not working.

I had the same problem and it turned out to be an Outlook issue. Outlook re-formats text based emails by removing extra line breaks. You can click "We removed extra line breaks in this message -> Restore line breaks" in the header of the individual email, or change the setting that does this nasty little trick "Options->Mail->Message Format->Remove extra line breaks in plain text messages"

The workaround (since you can't control the settings on every potential email target) I found here Newsletter Formatting And The Remove Extra Line Breaks Issue. Basically, if you add two white space characters to the beginning of each line, Outlook won't reformat the email.

Here's an extension method to help (method name is a bit verbose so change to your liking :))

namespace System.Text
{
    public static class StringBuilderExtensions
    {
        public static void AppendLineWithTwoWhiteSpacePrefix(this StringBuilder sb, string value)
        {
            sb.AppendFormat("{0}{1}{2}", "  ", value, Environment.NewLine);
        }

        public static void AppendLineWithTwoWhiteSpacePrefix(this StringBuilder sb)
        {
            sb.AppendFormat("{0}{1}", "  ", Environment.NewLine);
        }
    }
}