Create and use login validation user control in ASP.NET

Introduction

Here we will discuss about user controls in Asp. net. Why we used user controls.

A user control is a kind of composite control that works much like an ASP. NET Web page—you can add existing Web server controls and markup to a user control, and define properties and methods for the control. You can then embed them in ASP.NET Web pages, where they act as a unit.

Create Login User Control

Now we are going to make a login Control which validates whether the entered text in the control is valid or not. If there is any textbox empty then it will show a validation to fill the textbox values. It will display an error which shows that something going wrong. It will also fire events that if both the value of user id and password is correct then raise login successfully, other wise it will raise event which shows login failed.

Step 1:

Firstly you have to start Visual Studio 2010 and take a Window Forms Control Library and set the controls on.

Take two label named as User Id and Password

Take two textbox and a button on window form and a error provider control.

Step 2:

Now we have to start to write the Code for our Control:-

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Drawing;
using System.Data;
using System.Linq;
using System.Text;
using System.Windows.Forms;
 
namespace WindowsFormsControlLibrary1
{
    public partial class UserControl1 : UserControl
    {       
        private System.Windows.Forms.StatusBar stbMessage;       
        public delegate void EventHandler(Object sender, EventArgs e);
        public event EventHandler SuccessfullyLogin;
        public event EventHandler LoginFail;
        //Constructor of the class
        public UserControl1()
        {
            InitializeComponent();
        }
        // This is the very simple Login Check Validation
        // The Password mus be ... "secret" .....
        private bool LoginCheck(string pName, string pPassword)
        {
            return pPassword.Equals("secret");
        }
 
        // Validate Login, in any case call the LoginSuccess or
        // LoginFailed event, which will notify the Application's
        // Event Handlers.
 
        private void button1_Click(object sender, EventArgs e)
        {
           // User Name Validation
                if (txtnam.Text.Length == 0)
                {
                    errorpro.SetError(txtnam,"Please enter a user name");
                    stbMessage.Text = "Please enter a user name";
                    return;
                }
                else
                {
                    errorpro.SetError(txtnam,"");
                    stbMessage.Text = "";
                }
 
                // Password Validation
                if (txtpw.Text.Length == 0)
                {
                    errorpro.SetError(txtpw,"Please enter a password");
                    stbMessage.Text = "Please enter a password";
                    return;
                }
                else
                {
                    errorpro.SetError(txtpw,"");
                    stbMessage.Text = "";
                }
 
                // Check Password
                if (LoginCheck(txtnam.Text, txtpw.Text))
                {
                    // If there any Subscribers for the LoginSuccess
                    // Event, notify them ...
                    if (SuccessfullyLogin != null)
                    {
                        SuccessfullyLogin(this, new System.EventArgs());
                    }
                }
                else
                {
                    // If there any Subscribers for the LoginFailed
                    // Event, notify them ...

                    if (LoginFail != null)
                    {
                        LoginFail(this, new System.EventArgs());
                    }
                }
            }
        // Read-Write Property for User Name Label
            public string LabelName
            {
                get
                {
                    return lblname.Text;
                }
                set
                {
                    lblname.Text = value;
                }
            }
 
            // Read-Write Property for User Name Password
            public string LabelPassword
            {
                get
                {
                    return lbpwd.Text;
                }
                set
                {
                    lbpwd.Text = value;
                }
            }
 
            // Read-Write Property for Login Button Text
            public string LoginButtonText
            {
                get
                {
                    return btnlg.Text;
                }
                set
                {
                    btnlg.Text = value;
                }
            }
 
            // Read-Only Property for User Name
            [Browsable(false)]
            public string UserName
            {
                set
                {
                    txtnam.Text = value;
                }
            }
 
            // Read-Only Property for Password
            [Browsable(false)]
            public string Password            {
                set
                {
                    txtpw.Text = value;
                }
            } 
        }
    }

Step 4: Open New Window Application and Add a  Reference Of .dll file which we created. Write the code given below.

Code :

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace TestApp
{
    public partial class Form1 : Form
    {
        [STAThread]
        static void Main()
        {
            Application.Run(new TestApp());
        }

        // This Event is fired by the Login Validation User Control
        private void LoginFailed(object sender, System.EventArgs e)
        {
            MessageBox.Show("Login falied ....", "Login Validation",
                MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
        }

        // This Event is fired by the Login Validation User Control|
        private void LoginSuccess(object sender, System.EventArgs e)
        {
            MessageBox.Show("Login success ....", "Login Validation",
                MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
        }
    }
}

Step 5: Double click on the dll file.

Step 6: Test application and press F5 again.