Writing a mail sender?

Question

hello to all i just started with c # and want to write a code for school project a mailer basically I want to send mails to all the emails saved in a txt file.

class Program
{
    static void Main(string[] args)
    {
        var client = new SmtpClient("smtp.gmail.com", 587)
        {
            Credentials = new NetworkCredential("myusername@gmail.com", "mypwd"),
            EnableSsl = true
        };
        client.Send("myusername@gmail.com", "myusername@gmail.com", "test", "testbody");
        Console.WriteLine("Sent");
        Console.ReadLine();
    }
}

with this code I can send only to a single e mail address i want a function to send e mails to all the email address i saved in txt file one by one with multi thread HOW CAN I DO THIS??

Answer 1

EDIT: Using comment from Ryan Wilson

Very easy to do using the following:

List<string> toAddresses = new List<string>(); // get from file using any chosen way

List<Task> tasks = new List<Task>();

var client = new SmtpClient("smtp.gmail.com", 587)
{
    Credentials = new NetworkCredential("myusername@gmail.com", "mypwd"),
    EnableSsl = true
};

foreach (var item in toAddresses)
{
    tasks.Add(client.SendMailAsync("myusername@gmail.com", item, "subject", "body"));
    Console.WriteLine($"Email sent to {item}");
}

await Task.WhenAll(tasks);

Console.ReadLine();

Or you can make use of Parallel.ForEach from Task Parallel Library .