ASP.net mvc5 每 7 天发送一次电子邮件？

Question

I'm working on a small project of mine and I'm not sure if what I am trying to do is possible on a web based solution.

And right now it's setup like this, a user post something and that date he posted in the database. What I want to do is if the user doesn't post another thing within 7 days I want to send them an email saying they are "late" or something similar to that.

I know how to send a email in asp.net as my user can request a new password / they need to verify their email. I just don't know how to set it up like I want above ( IF that even is possible )

Answer 1

You need a separate process that checks for, and then sends, the emails. You won't be able to do it in the web application itself, but some kind of service would do it.

This service would just need to periodically check your database for users and the last date they posted. If it's more than 7 days, send that email off.

Remember to record that the email has been sent and check this when determining what emails to send, otherwise you'll get an email sent every time the service checks the database, which might frustrate the user a bit!

Answer 2

sending email in asp is simple. its a code i did before that check if you want to send a file too:

for working with time you have to work with timeSpan and dateTime

its from example in stackoverflow: Assuming StartDate and EndDate are of type DateTime:

(EndDate - StartDate).TotalDays

you have to check if this value is bigger than 7

so code for sending mail is like below but you have to optimize it for your own:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Net.Mail;

public partial class SendMail : System.Web.UI.Page
{
MailMessage mail = new MailMessage();
protected void Page_Load(object sender, EventArgs e)
{

}
protected void btnSend_Click(object sender, EventArgs e)
{

try
{
lblmessage.Text ="";
mail.To.Add(txtto.Text.Trim());
mail.From = new MailAddress(txtfrom.Text.Trim());
mail.Subject = txtsubject.Text.Trim();
mail.Body = txtbody.Text.Trim();
mail.IsBodyHtml = true;
if (uploader.HasFile)
{
string filename = uploader.PostedFile.FileName;
string filepath=Server.MapPath("uploads//"+filename);
uploader.SaveAs(filepath);
Attachment attach = new Attachment(filepath);
attach.TransferEncoding = System.Net.Mime.TransferEncoding.Base64;
mail.Attachments.Add(attach);
}

SmtpClient client = new SmtpClient();

client.Host = "mail.youdomain.com";
client.Credentials = new System.Net.NetworkCredential("email username=info@yourdomain.com", "email passowrd");
client.Send(mail);
lblmessage.Text = "sent with success";
}
catch (Exception ex)
{
lblmessage.Text = ex.Message;
}
}

}