Checking validations for user controls in Windows Application using C#.net. || Email validation in Windows Application using C#.net.

To implement the validations for user controls in Windows Forms Application you need to follow the below steps :

Step1 :
First you need to design a table and create a stored procedure in Ms Access 2007 to insert the records into database.

Step2:
On the File menu, click New Project. Select Windows Forms Application as your project type.
Design the Form using controls from Toolbox.

Step3: 

Now open the Form.cs page and write the following source code.

Form.cs 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;

using System.Data.OleDb;

using System.Text.RegularExpressions;

 

namespace Sample

{

    public partial class Sample_Example : Form

    {

        OleDbConnection con = new OleDbConnection(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|\App_Data\SampleDB.accdb; Jet OLEDB:Database Password=1234;Persist Security Info=False");

        public Sample_Example()

        {

            InitializeComponent();

        }

        private void btnSave_Click(object sender, EventArgs e)

        {

            con.Open();

            OleDbDataAdapter da = new OleDbDataAdapter("Select * from SampleDB_CreateClient Where Client_Name='" + txtClientName.Text + "'  ", con);

            DataTable dt = new DataTable();

            da.Fill(dt);

            con.Close();

            if (txtClientName.Text == string.Empty || txtContactPerson.Text == string.Empty || txtAdress.Text == string.Empty || txtContactNo.Text == string.Empty || txtEmailId.Text == string.Empty)

            {

                MessageBox.Show("Please fill all the fields.", "Alert!!");

            }

            else if (dt.Rows.Count > 0)

            {

                MessageBox.Show("Client name already exists.", "Warning");

            }

            else

            {

                string pattern = null;

                pattern = "^([0-9a-zA-Z]([-\\.\\w]*[0-9a-zA-Z])*@([0-9a-zA-Z][-\\w]*[0-9a-zA-Z]\\.)+[a-zA-Z]{2,9})$";

                if (Regex.IsMatch(txtEmailId.Text, pattern))

                {

                    OleDbCommand cmd = new OleDbCommand("SampleDB_ClientInsert", con);

                    cmd.CommandType = CommandType.StoredProcedure;

                    cmd.Parameters.AddWithValue("@Client_Name", txtClientName.Text);

                    cmd.Parameters.AddWithValue("@Contact_Person", txtContactPerson.Text);

                    cmd.Parameters.AddWithValue("@Address", txtAdress.Text);

                    cmd.Parameters.AddWithValue("@Contact_No", txtContactNo.Text);

                    cmd.Parameters.AddWithValue("@Email_Id", txtEmailId.Text);

                    cmd.Parameters.AddWithValue("@CreatedDate", System.DateTime.Now.ToString("dd/MM/yyyy"));

                    con.Open();

                    int result = 0;

                    result = cmd.ExecuteNonQuery();

                    con.Close();

                    if (result > 0)

                    {

                        MessageBox.Show("Record inserted successfully.", "Alert");

                    }

                    this.Close();

                }

                else

                {

                    MessageBox.Show("Invalid email address");

                }

            }

        }

    }

} 

 

Step4:
Now build the Solution and Debug it for the output.