protected void LinkButton1_Click(object sender, EventArgs e)
    {
        if (TextBox1.Text != "")
        {
            reg.checkusername1 = TextBox1.Text;
            int x = reg.checkavailability();
            if (x == 1)
            {
               // ScriptManager.RegisterStartupScript(this, this.GetType(), "dg", "", false);
            }
            else
            {
               // ScriptManager.RegisterStartupScript(this, this.GetType(), "dg", "", false);
            }
        }
        else
        {
           // ScriptManager.RegisterStartupScript(this, this.GetType(), "dg", "", false);
        }
    }


///////////////Class File////////////

public int checkavailability()
        {
            if (conn.State == ConnectionState.Open)
            {
                conn.Close();
            }
            conn.Open();
            SqlCommand cmd = new SqlCommand("checkavailability", conn);
            cmd.CommandType = CommandType.StoredProcedure;
            SqlParameter param = new SqlParameter();
            param.Direction = ParameterDirection.ReturnValue;
            param = cmd.Parameters.Add("@username", SqlDbType.VarChar, 100);
            param.Direction = ParameterDirection.Input;
            param.Value = checkusername;
            param = cmd.Parameters.Add("@flag", SqlDbType.Int);
            param.Direction = ParameterDirection.ReturnValue;
            cmd.ExecuteNonQuery();
            return Convert.ToInt32(cmd.Parameters["@flag"].Value.ToString());
        }

/////////Stored Procedure//////////////

ALTER PROCEDURE [dbo].[checkavailability]
@username varchar(100)
AS
BEGIN
declare @flag int
select @flag=count(*) from userregistration where username=@username
	if(@flag<>0)
begin

return 1
end
else
begin 
return 2
end
END