In this article I will explain with an example, how to send email using Web Service in ASP.Net using C# and VB.Net.
In this article, Gmail SMTP Mail Server will be used for sending emails.
To send email with Gmail SMTP Server, you will need to use an email address and password of a valid Gmail account and along with that you will need the Gmail SMTP Mail Server settings.
 
 

HTML Markup

The HTML Markup consists of following controls:
TextBox – For capturing the values of Recipient Email address, Subject and Body.
The TextBox for Body has been set with the TextMode property to MultiLine i.e. HTML TextArea.
Button – For sending email.
The Button has been assigned with an OnClick event handler.
<table border="0" cellpadding="0" cellspacing="0">
    <tr>
        <td>To:</td>
        <td>
            <asp:TextBox ID="txtTo" runat="server" /></td>
    </tr>
    <tr>
        <td>Subject:</td>
        <td>
            <asp:TextBox ID="txtSubject" runat="server" /></td>
    </tr>
    <tr>
        <td valign="top">Body:</td>
        <td>
            <asp:TextBox ID="txtBody" runat="server" TextMode="MultiLine" Height="150" Width="200" /></td>
    </tr>
    <tr>
        <td></td>
        <td>
            <asp:Button ID="btnSend" Text="Send" runat="server" /></td>
    </tr>
</table>
 
 

Mail Server Settings in Web.Config file

The following Mail Server settings need to be saved in the Web.Config file.
<system.net>
    <mailSettings>
        <smtp deliveryMethod="Network" from="sender@gmail.com">
            <network
                host="smtp.gmail.com"
                port="587"
                enableSsl="true"
                userName="sender@gmail.com"
                password="SenderGmailPassword"
                defaultCredentials="true"/>
       </smtp>
    </mailSettings>
</system.net>
 

MailMessage Class Properties

Following are the required properties of the MailMessage class.
From – Sender’s email address.
To – Recipient(s) Email Address.
CC – Carbon Copies. (If any)
BCC – Blind Carbon Copies. (If any)
Subject – Subject of the Email.
Body – Body of the Email.
IsBodyHtml – Specify whether body contains text or HTML mark up.
Attachments – Attachments. (If any)
ReplyTo – ReplyTo Email address.
 

SMTP Class Properties

Following are the properties of the SMTP class.
Host – SMTP Server URL. (Gmail: smtp.gmail.com)
EnableSsl – Specify whether your host accepts SSL Connections. (Gmail: True)
UseDefaultCredentials – Set to True in order to allow authentication based on the Credentials of the Account used to send emails.
Credentials – Valid login credentials for the SMTP server. (Gmail: email address and password)
Port – Port Number of the SMTP server. (Gmail: 587)
 
 

Namespaces

You will need to import the following namespaces.
C#
using System.Net;
using System.Net.Mail;
using System.Web.Services;
using System.Configuration;
using System.Net.Configuration;
 
VB.Net
Imports System.Net
Imports System.Net.Mail
Imports System.Web.Services
Imports System.Configuration
Imports System.Net.Configuration
 
 

Adding Web Service

You will need to add a new Web Service (ASMX) file using Add New Item Dialog of Visual Studio as shown below.
Send Email using Web Service in ASP.Net using C# and VB.Net
 
 

Configuring Web Service to handle jQuery AJAX calls

By default, the Web Service will not accept requests from client side sent using jQuery AJAX. In order to allow a Web Service handle jQuery AJAX calls, the ScriptService attribute needs to be specified to the Web Service class.
The following Web Service consists of a Web Method SendEmail, which accepts email address (toEmail), Subject and Body parameters and returns the String message.
The Sender email address (from) is fetched from the SmtpSection of the Web.Config file.
All these values are set into an object of the MailMessage class.
Then, object of the SmtpClient class is created and the settings of the Mail Server such has Host, Port, DefaultCredentials, EnableSsl, Username and Password are fetched from the mailSettings section of the Web.Config file and attached to the SmtpClient class object.
Note: For more details on how to send email in ASP.Net, please refer my article Send email using Gmail SMTP Mail Server in ASP.Net.
 
Finally, a String message is returned.
C#
/// <summary>
/// Summary description for Service
/// </summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
// To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line.
[System.Web.Script.Services.ScriptService]
public class Service : System.Web.Services.WebService
{
 
    public Service()
    {
        //Uncomment the following line if using designed components
        //InitializeComponent();
    }
 
    [WebMethod]
    public string SendEmail(string toEmail, string subject, string body)
    {
        //Read SMTP section from Web.Config.
        SmtpSection smtpSection = (SmtpSection)ConfigurationManager.GetSection("system.net/mailSettings/smtp");
        using (MailMessage mm = new MailMessage(smtpSection.From, toEmail))
        {
            //Setting Subject and Body.
            mm.Subject = subject;
            mm.Body = body;
            mm.IsBodyHtml = false;
 
            // Sending email
            using (SmtpClient smtp = new SmtpClient())
            {
                smtp.Host = smtpSection.Network.Host;
                smtp.EnableSsl = smtpSection.Network.EnableSsl;
                NetworkCredential networkCred = new NetworkCredential(smtpSection.Network.UserName, smtpSection.Network.Password);
                smtp.UseDefaultCredentials = smtpSection.Network.DefaultCredentials;
                smtp.Credentials = networkCred;
                smtp.Port = smtpSection.Network.Port;
                smtp.Send(mm);
            }
        }
        return "Email sent.";
    }
}
 
VB.Net
' To allow this Web Service to be called from script, using ASP.NET AJAX, uncomment the following line.
<System.Web.Script.Services.ScriptService()>
<WebService(Namespace:= "http://tempuri.org/")>
<WebServiceBinding(ConformsTo:= WsiProfiles.BasicProfile1_1)>
<Global.Microsoft.VisualBasic.CompilerServices.DesignerGenerated()>
Public Class Service
    Inherits System.Web.Services.WebService
 
    <WebMethod()>
    Public Function SendEmail(ByVal toEmail As String, ByVal subject As String, ByVal body As String) As String
 
        'Read SMTP section from Web.Config.
        Dim smtpSection As SmtpSection = CType(ConfigurationManager.GetSection("system.net/mailSettings/smtp"),SmtpSection)
        Using mm As MailMessage = New MailMessage(smtpSection.From, toEmail)
 
            'Setting Subject and Body.
            mm.Subject = subject
            mm.Body = body
            mm.IsBodyHtml = False
 
            'Sending email
            Using smtp As SmtpClient = New SmtpClient()
                smtp.Host = smtpSection.Network.Host
                smtp.EnableSsl = smtpSection.Network.EnableSsl
                Dim networkCred As NetworkCredential = New NetworkCredential(smtpSection.Network.UserName, smtpSection.Network.Password)
                smtp.UseDefaultCredentials = smtpSection.Network.DefaultCredentials
                smtp.Credentials = networkCred
                smtp.Port = smtpSection.Network.Port
                smtp.Send(mm)
            End Using
        End Using
        Return "Email sent."
    End Function
End Class
 
 

jQuery AJAX function to send emails using Web Service in ASP.Net

When the Send Button is clicked, a jQuery AJAX call to the Web Service is made and the ToEmail, Subject and Body values are fetched from the TextBoxes and are passed as parameters to the Web Method SendEmail.
Finally, the value returned from the Web Services Web Method is fetched inside the Success event handler of the jQuery AJAX function and displayed using JavaScript Alert Message Box.
<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js"></script>
<script type="text/javascript">
    $(function () {
        $("[id*= btnSend]").click(function () {
            var toEmail = $.trim($("[id*= txtTo]").val());
            var subject = $.trim($("[id*= txtSubject]").val());
            var body = $.trim($("[id*= txtBody]").val());
            $.ajax({
                 type: "POST",
                 url: "Service.asmx/SendEmail",
                 data: "{ toEmail: '" + toEmail + "', subject: '" + subject + "', body: '" + body + "' }",
                 contentType: "application/json; charset=utf-8",
                 dataType: "json",
                 success: function (r) {
                    alert(r.d);
                },
                 error: function (r) {
                    alert(r.responseText);
                },
                 failure: function (r) {
                    alert(r.responseText);
                }
            });
            return false;
        });
    });
</script>
 
 

Screenshots

Email Form

Send Email using Web Service in ASP.Net using C# and VB.Net
 

Received Email

Send Email using Web Service in ASP.Net using C# and VB.Net
 
 

Downloads

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