Restore SQL Server Backup File With C#

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.Diagnostics;
using System.Data.SqlClient;
namespace SQLBackUpApp
{
    public partial class Form1 : Form
    {
        SqlConnection con;
        SqlCommand cmd;
        SqlDataReader dr;
        public Form1()
        {
            InitializeComponent();
        }
        private void Form1_Load(object sender, EventArgs e)
        {
            label3.Visible = false;
            serverName(".");          
        }
        public void serverName(string str)
        {
            con = new SqlConnection("Data Source=" + str + ";Database=Master;data source=.; uid=sa; pwd=Micr0s0ft;");
            con.Open();
            cmd = new SqlCommand("select *  from sysservers  where srvproduct='SQL Server'", con);
            dr = cmd.ExecuteReader();
            while (dr.Read())
            {
                ComboBoxserverName.Items.Add(dr[2]);
            }
            dr.Close();
        }
        public void Createconnection()
        {
            con = new SqlConnection("Data Source=" + (ComboBoxserverName.Text) + ";Database=Master;data source=.; uid=sa; pwd=Micr0s0ft;");
            con.Open();
            ComboBoxDatabaseName.Items.Clear();
            cmd = new SqlCommand("select * from sysdatabases", con);
            dr = cmd.ExecuteReader();
            while(dr.Read())
            {
                ComboBoxDatabaseName.Items.Add(dr[0]);
            }
            dr.Close();
        }
        public void query(string que)
        {
            // ERROR: Not supported in C#: OnErrorStatement
            cmd = new SqlCommand(que, con);
            cmd.ExecuteNonQuery();
        }
        public void blank(string str)
        {
            if (string.IsNullOrEmpty(ComboBoxserverName.Text) | string.IsNullOrEmpty(ComboBoxDatabaseName.Text))
            {
                // label3.Visible = true;
                MessageBox .Show("Server Name & Database can not be Blank");
                return;
            }
            else
            {                 
               if (str == "restore")
               {
                   OpenFileDialog1.ShowDialog();
                   // string a = ComboBoxDatabaseName.Text.ToString();
                   query("IF EXISTS (SELECT name FROM master.dbo.sysdatabases WHERE name = N'" + ComboBoxDatabaseName.Text + "') DROP DATABASE " + ComboBoxDatabaseName.Text + " RESTORE DATABASE " + ComboBoxDatabaseName.Text + " FROM DISK = '" + OpenFileDialog1.FileName + "'");
                   label3.Visible = true;
                   label3.Text = "Database Backup file has been restore successfully";     
               }
            }
        }
        private void ComboBoxserverName_SelectedIndexChanged(object sender, EventArgs e)
        {
            Createconnection();
        }
        private void cmbrestore_Click(object sender, EventArgs e)
        {
            blank("restore");
        }
    }
}

In the code above you can change the connection string corresponding to your database.

Now run the application and select the server name and database name to restore the database backup file.

Now click on the "Restore" Button and select the backup file location from the disk.

Now open the selected database to see the backup file data.