From Zero to Email Hero: A Beginner's Guide to Sending Email in C#

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Create database db_Test
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CREATE TABLE Student(
[Name][nvarchar](50) NULL, [DOB][date] NULL, [Email][nvarchar](150) NULL, [Mob][nvarchar](50) NULL)
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INSERT[Student]([Name], [DOB], [Email], [Mob]) VALUES(N 'a', CAST(N '1990-01-01'
AS Date), N '[email protected]', N '555555555')
INSERT[dbo].[Student]([Name], [DOB], [Email], [Mob]) VALUES(N 'b', CAST(N '1990-04-04'
AS Date), N '[email protected]', N '777777777')
INSERT[dbo].[Student]([Name], [DOB], [Email], [Mob]) VALUES(N 'c', CAST(N '1992-05-08'
AS Date), N '[email protected]', N '88888888')

private void SendEmail_Load(object sender, EventArgs e) {  
    SqlConnection sqlConnection = new SqlConnection();  
    sqlConnection.ConnectionString = "server = YOURSERVERNAME; database = YOURDBNAME; User ID = sa; Password = YOURPASSWORD"; //Connection Details  
    //select fields to mail example student details  
    SqlCommand sqlCommand = new SqlCommand("select Name,DOB,Email,Mob from Student", sqlConnection); //select query command  
    SqlDataAdapter sqlDataAdapter = new System.Data.SqlClient.SqlDataAdapter();  
    sqlDataAdapter.SelectCommand = sqlCommand; //add selected rows to sql data adapter  
    DataSet dataSetStud = new DataSet(); //create new data set  
    try {  
        sqlDataAdapter.Fill(dataSetStud, "student"); //fill sql data adapter rows to data set  
        dgStudent.ColumnCount = 4;  
        dgStudent.Columns[0].HeaderText = "Student Name";  
        dgStudent.Columns[0].DataPropertyName = "Name";  
        dgStudent.Columns[1].HeaderText = "Date of birth";  
        dgStudent.Columns[1].DataPropertyName = "DOB";  
        dgStudent.Columns[2].HeaderText = "Mail Id";  
        dgStudent.Columns[2].DataPropertyName = "Email";  
        dgStudent.Columns[3].HeaderText = "Mobile No";  
        dgStudent.Columns[3].DataPropertyName = "Mob";  
        dgStudent.DataSource = dataSetStud;  
        dgStudent.DataMember = "student";  
    } catch (Exception Ex) {  
        System.Windows.Forms.MessageBox.Show(Ex.Message);  
        sqlConnection.Close();  
    }  
}  

public static string getHtml(DataGridView grid) {  
    try {  
        string messageBody = "<font>The following are the records: </font><br><br>";  
        if (grid.RowCount == 0) return messageBody;  
        string htmlTableStart = "<table style=\"border-collapse:collapse; text-align:center;\" >";  
        string htmlTableEnd = "</table>";  
        string htmlHeaderRowStart = "<tr style=\"background-color:#6FA1D2; color:#ffffff;\">";  
        string htmlHeaderRowEnd = "</tr>";  
        string htmlTrStart = "<tr style=\"color:#555555;\">";  
        string htmlTrEnd = "</tr>";  
        string htmlTdStart = "<td style=\" border-color:#5c87b2; border-style:solid; border-width:thin; padding: 5px;\">";  
        string htmlTdEnd = "</td>";  
        messageBody += htmlTableStart;  
        messageBody += htmlHeaderRowStart;  
        messageBody += htmlTdStart + "Student Name" + htmlTdEnd;  
        messageBody += htmlTdStart + "DOB" + htmlTdEnd;  
        messageBody += htmlTdStart + "Email" + htmlTdEnd;  
        messageBody += htmlTdStart + "Mobile" + htmlTdEnd;  
        messageBody += htmlHeaderRowEnd;  
        //Loop all the rows from grid vew and added to html td  
        for (int i = 0; i <= grid.RowCount - 1; i++) {  
            messageBody = messageBody + htmlTrStart;  
            messageBody = messageBody + htmlTdStart + grid.Rows[i].Cells[0].Value + htmlTdEnd; //adding student name  
            messageBody = messageBody + htmlTdStart + grid.Rows[i].Cells[1].Value + htmlTdEnd; //adding DOB  
            messageBody = messageBody + htmlTdStart + grid.Rows[i].Cells[2].Value + htmlTdEnd; //adding Email  
            messageBody = messageBody + htmlTdStart + grid.Rows[i].Cells[3].Value + htmlTdEnd; //adding Mobile  
            messageBody = messageBody + htmlTrEnd;  
        }  
        messageBody = messageBody + htmlTableEnd;  
        return messageBody; // return HTML Table as string from this function  
    } catch (Exception ex) {  
        return null;  
    }  
}  

Step 5. Send email using SMTP

Now, let's create a method to send an email with this HTML format string as the body of the mail. Before creating this function, add two namespaces given below.

using System.Net;
using System.Net.Mail;

The Email method is listed below. As you can see from the below code, the method Email takes HTML as a string. A new MailMessage is created with From, To and other properties. SmtpClient is created with a Port, Host, and other properties. In the end, the Send method is used to send the email.

public static void Email(string htmlString) {  
    try {  
        MailMessage message = new MailMessage();  
        SmtpClient smtp = new SmtpClient();  
        message.From = new MailAddress("FromMailAddress");  
        message.To.Add(new MailAddress("ToMailAddress"));  
        message.Subject = "Test";  
        message.IsBodyHtml = true; //to make message body as html  
        message.Body = htmlString;  
        smtp.Port = 587;  
        smtp.Host = "smtp.gmail.com"; //for gmail host  
        smtp.EnableSsl = true;  
        smtp.UseDefaultCredentials = false;  
        smtp.Credentials = new NetworkCredential("FromMailAddress", "password");  
        smtp.DeliveryMethod = SmtpDeliveryMethod.Network;  
        smtp.Send(message);  
    } catch (Exception) {}  
}  

Step 6. Email SMTP Settings

Email To use this function given above, you need to pass a string (string, which you wanted in the mail body) to it. Here, in this function, I have configured uses the Gmail host only. If your “from address” is different from Gmail, then you have to set that Server port number, host name and SSL property. Some Server names are given below.

Server Name	SMTP Address	Port	SSL
Yahoo!	smtp.mail.yahoo.com	587	Yes
GMail	smtp.gmail.com	587	Yes
Hotmail	smtp.live.com	587	Yes

Step 7. Send email

Now, let's use these functions to send GridView data as an email on a button click, as shown below.

private void btnSent_Click(object sender, EventArgs e) {  
    string htmlString = getHtml(dgStudent); //here you will be getting an html string  
    Email(htmlString); //Pass html string to Email function.  
}  

Step 8. Build and run

Now, run and click “send an email” button. Check that you will be getting an Email to “to address”, which you provide and the output is shown below.

Summary

In this article, we learned how to build an email client app in C#, store emails in a database, read emails, and send emails to the email addressed listed in the database.