Registration + Login + Email-id verification Scenario in C#

Introduction

Normally as a user we navigate to a website, register ourself and verify the account to enjoy the service provided by them. To develop such an application we need a special scenario. There are many ways to perform the activation. 

Send the SMS containing random code to cell phone and ask that code for verification
Send email having URL to verify
Send email having random code to verify

In this article, we will learn the (2) method. In the future, I'll post on all.

Look at the following file hierarchy and develop the same by following the steps given below.

Untitled1.jpg

Follow the steps for development:

Step 1

Develop the database, look at the screenshot:

Untitled.jpg

Remember to mark the "id" field as auto-number and the default value for verified column to "NO".

Step 2

Create the connection string in config file as follows:
<connectionStrings>
<add name="ConnectionString1" connectionString="Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database.mdf;Integrated Security=True;User Instance=True"
providerName="System.Data.SqlClient" />
</connectionStrings>

Step 3

Configure the secure location path that will be accessed when the user is fully authorized.

<location path="secure">
<system.web>
<authorization>
<deny users="?"/>
</authorization>
</system.web>
</location>


Step 4

Create the ~/login/Register.aspx form using C# code-behind and write the following code.

Register.aspx Code


<form id="form1" runat="server">
<div>
<asp:Label ID="Label1" runat="server" Visible="False" ForeColor="Red" Font-Bold="True"></asp:Label><br />
<br />
<table cellpadding="5px" cellspacing="5px">
<tr>
<td style="vertical-align:top;">
Full Name:
</td>
<td style="vertical-align:top;">
<asp:TextBox ID="fullname" runat="server" Width="200px" MaxLength="50"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server"
ErrorMessage="Full Name can't be empty." ControlToValidate="fullname" ForeColor="Red">*</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td style="vertical-align:top;">
Email ID:
</td>
<td style="vertical-align:top;">
<asp:TextBox ID="emailid" runat="server" Width="200px" MaxLength="80"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator2" runat="server"
ErrorMessage="Email ID can't be empty." ControlToValidate="emailid" ForeColor="Red">*</asp:RequiredFieldValidator>
<asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server"
ErrorMessage="Invalid Email ID." ControlToValidate="emailid" ForeColor="Red"
ValidationExpression="\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*">*</asp:RegularExpressionValidator>
</td>
</tr>
<tr>
<td style="vertical-align:top;">
Username:
</td>
<td style="vertical-align:top;">
<asp:TextBox ID="username" runat="server" Width="200px" MaxLength="20"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator3" runat="server"
ErrorMessage="Username can't be empty." ControlToValidate="username" ForeColor="Red">*</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td style="vertical-align:top;">
Password:
</td>
<td style="vertical-align:top;">
<asp:TextBox ID="password" runat="server" TextMode="Password" Width="200px" MaxLength="20"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator4" runat="server"
ErrorMessage="Password can't be empty." ControlToValidate="password"
ForeColor="Red">*</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td style="vertical-align:top;">
Re-Type Password:
</td>
<td style="vertical-align:top;">
<asp:TextBox ID="repassword" runat="server" TextMode="Password" Width="200px" MaxLength="20"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator6" runat="server"
ErrorMessage="Password can't be empty." ControlToValidate="password"
ForeColor="Red">*</asp:RequiredFieldValidator>
</td>
</tr>
</table>

<asp:Button ID="submit" runat="server" Text="Submit" onclick="submit_Click" />

<table>
<tr>
<td>
<asp:ValidationSummary ID="ValidationSummary1" runat="server" ForeColor="Red"/>
<br /><br />
<asp:HyperLink ID="HyperLink1" runat="server" NavigateUrl="~/login/login.aspx">I have already an account !</asp:HyperLink>
<br /><br />
</td>
</tr>
</table>
</div>
</form>


Register.aspx.cs Code


protected void Page_Load(object sender, EventArgs e)
{

}
protected void submit_Click(object sender, EventArgs e)
{
SqlDataSource sds = new SqlDataSource();
sds.ConnectionString = ConfigurationManager.ConnectionStrings["ConnectionString1"].ToString();
sds.SelectParameters.Add("username", TypeCode.String, this.username.Text);
sds.SelectCommand = "SELECT * FROM [users] WHERE [username] = @username";
DataView dv = (DataView)sds.Select(DataSourceSelectArguments.Empty);
try
{
if (dv.Count == 0)
{
SqlDataSource emailcheck = new SqlDataSource();
emailcheck.ConnectionString = ConfigurationManager.ConnectionStrings["ConnectionString1"].ToString();
emailcheck.SelectParameters.Add("emailid", TypeCode.String, this.emailid.Text);
emailcheck.SelectCommand = "SELECT * FROM [users] WHERE [emailid] = @emailid";
DataView emailcheckdv = (DataView)emailcheck.Select(DataSourceSelectArguments.Empty);

try
{
if (emailcheckdv.Count == 0)
{
if (password.Text == repassword.Text)
{
execution(fullname.Text, emailid.Text, username.Text, password.Text);
}
else
{
Label1.Visible = true;
Label1.Text = "Form not completed or password not matched.";
}
}
else
{
Label1.Visible = true;
Label1.Text = "Email ID already Registered.";
}
}
catch (System.Data.SqlClient.SqlException ex_msg)
{
string msg = "Error occured while login.";
msg += ex_msg.Message;
Label1.Visible = true;
Label1.Text = msg;
}
}
else
{
username.Text = null;
password.Text = null;
Label1.Visible = true;
Label1.Text = "User already exist, please use different username.";
}
}
catch (System.Data.SqlClient.SqlException ex_msg)
{
string msg = "Error occured while login.";
msg += ex_msg.Message;
Label1.Visible = true;
Label1.Text = msg;
}
finally
{
//Here will be fially elements
}
}

public string GetConnectionString()
{
return System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionString1"].ConnectionString;
}

public void execution(string fullname, string emailid, string username, string password)
{
SqlConnection myConnection = new SqlConnection(GetConnectionString());
SqlCommand storeimage = new SqlCommand("INSERT INTO users (fullname,emailid,username,password) VALUES (@fullname,@emailid,@username,@password)", myConnection);
storeimage.Parameters.Add("@fullname", SqlDbType.VarChar, 50).Value = fullname;
storeimage.Parameters.Add("@emailid", SqlDbType.VarChar, 50).Value = emailid;
storeimage.Parameters.Add("@username", SqlDbType.VarChar, 50).Value = username;
storeimage.Parameters.Add("@password", SqlDbType.VarChar, 50).Value = password;

try
{
myConnection.Open();
storeimage.ExecuteNonQuery();
sendmail(fullname, emailid, username, password);
Label1.Visible = true;
Label1.Text = "User Created.";
}
catch
{
//catch block goes here
}
}

public void sendmail(string fullname, string emailid, string username, string password)
{
string siteurl = "http://www.yourdomain.com/login/Activation.aspx";
string smsg = "New Registration on our website, find your details below:<br>";
smsg += "<br><b>Name: </b>" + fullname;
smsg += "<br><b>Username: </b>" + username;
smsg += "<br><b>Password: </b>" + password;
smsg += "<br><b>Your account is not activated still, please activate it by clicking here: </b>";
smsg += "<br><b>Title of Post: </b><br>" + "<a href=" + siteurl + "?username=" + username + "></a>";
smsg += "<br><br><br><br>";
smsg += "<b>Administrator";

MailMessage message = new MailMessage();
try
{
message.To.Add(new MailAddress(emailid));
message.From = new MailAddress("youremailaddress");

message.Subject = "yoursubject";
message.Body = smsg;
message.IsBodyHtml = true;
SmtpClient client = new SmtpClient();
client.Port = 25; // Gmail works on this port 587
client.Host = "smtp.gmail.com";
System.Net.NetworkCredential nc = new System.Net.NetworkCredential("youremailaddress", "password");
client.EnableSsl = true;
client.UseDefaultCredentials = false;
client.Credentials = nc;
client.Send(message);
}
catch
{
//catch block goes here
}
}


Step 5

Now, create the ~/login/Login.aspx form using C# code-behind and write the following code.

Login.aspx


<form id="form1" runat="server">
<div>
<table cellspacing="5px">
<tr>
<td>
<table>
<tr>
<td>
Username:
</td>
<td>
<asp:TextBox ID="username" runat="server" Width="150px"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator3" runat="server"
ErrorMessage="Username can't be empty." ControlToValidate="username" ForeColor="Red">*</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td>
Password:
</td>
<td>
<asp:TextBox ID="password" runat="server" TextMode="Password" Width="150px"></asp:TextBox>
<asp:RequiredFieldValidator ID="RequiredFieldValidator4" runat="server"
ErrorMessage="Password can't be empty." ControlToValidate="password"
ForeColor="Red">*</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td>

</td>
<td>
<asp:Button ID="login" runat="server" Text="login" onclick="login_Click" />
</td>
</tr>
</table>
</td>
</tr>
</table>

<br /><br />

<table>
<tr>
<td>
<asp:Label ID="lblinfo" runat="server" Text=""></asp:Label><br />
<asp:ValidationSummary ID="ValidationSummary1" runat="server" ForeColor="Red"/>
</td>
</tr>
</table>

</div>
</form>


Login.aspx.cs Code


protected void Page_Load(object sender, EventArgs e)
{

}
protected void login_Click(object sender, EventArgs e)
{
SqlDataSource sds = new SqlDataSource();
sds.ConnectionString = ConfigurationManager.ConnectionStrings["ConnectionString1"].ToString();

sds.SelectParameters.Add("username", TypeCode.String, this.username.Text);
sds.SelectParameters.Add("password", TypeCode.String, this.password.Text);

sds.SelectCommand = "SELECT * FROM [users] WHERE [username] = @username AND [password] = @password";

DataView dv = (DataView)sds.Select(DataSourceSelectArguments.Empty);
try
{
if (dv.Count == 0)
{
this.lblinfo.ForeColor = System.Drawing.Color.Red;
this.lblinfo.Text = "Invalid username or password.";
return;
}
else
{

//stop the user here if not verified otherwise let him go


FormsAuthentication.RedirectFromLoginPage(username.Text, true);
Session["username"] = username.Text;
//Response.Redirect("~/admin/publisharticle.aspx");
}
}
catch (System.Data.SqlClient.SqlException ex_msg)
{
string msg = "Error occured while login.";
msg += ex_msg.Message;
throw new Exception(msg);
}
finally
{
//Here will be fially elements

}
}


In above code, look at line [//stop
the user here if not verified otherwise let him go]. Here you can put your decision that you are wishing to let the access to un-verified user or not. Place the code as you wish.

Step 6

Now, create the ~/login/Activation.aspx form using C# code-behind and write the following code.

Activation.aspx Code

<form id="form1" runat="server">
<div>
<asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>
</div>
</form>

Activation.aspx.cs Code

protected void Page_Load(object sender, EventArgs e)
{
string usernamequerystring = Request.QueryString["username"].ToString();

SqlConnection myConnection = new SqlConnection(GetConnectionString());
SqlCommand storeimage = new SqlCommand("UPDATE users SET verified='YES' WHERE username=@usernamequerystring)", myConnection);
storeimage.Parameters.Add("@usernamequerystring", SqlDbType.VarChar, 50).Value = usernamequerystring;

try
{
myConnection.Open();
storeimage.ExecuteNonQuery();
Label1.Visible = true;
Label1.Text = "Account Activated.";
}
catch
{
//catch block goes here
}
}
public string GetConnectionString()
{
return System.Configuration.ConfigurationManager.ConnectionStrings["ConnectionString1"].ConnectionString;
}

That's all for the coding. The secure folder can have any page. No special code here.

Conclusion

In this article I have only outlined the basic procedures for such an application.

HAVE A GREAT CODING !!