validation using javascript in asp.net

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="WebForm1.aspx.cs" Inherits="Insert.WebForm1" %>





 
 


 
 
 





using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Data.SqlClient;
namespace Insert
{
  public partial class WebForm1 : System.Web.UI.Page
  {
  string strConnString = ConfigurationManager.ConnectionStrings["ConnectionString"].ConnectionString;
  SqlCommand com;
 
  protected void Button1_Click(object sender, EventArgs e)
  {
  if (txt_name.Text == "")
  {
  txt_name.Focus();
  }

  else
  {
  SqlConnection con = new SqlConnection(strConnString);
  con.Open();
  com = new SqlCommand();
  com.Connection = con;
  com.CommandType = CommandType.Text;
  com.CommandText = @"INSERT INTO register(name)VALUES(@name)";
  com.Parameters.AddWithValue("@name", txt_name.Text);
  com.ExecuteNonQuery();
  con.Close();
  Label1.Text = "Data entered successfully!!!";
  }
 

  }
  }
}