How Do I Add Details Inside A Form And Then Transfer The Details Into Datagridview

//frm declaration

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

namespace Test
{
    public partial class FrmDeclaration : Form
    {
        public FrmDeclaration()
        {
            InitializeComponent();
        }

        private void btnAdd_Click(object sender, EventArgs e)
        {
            FrmDetails FrmDetails = new FrmDetails();
            FrmDetails.DetailUpdated += new FrmDetails.DetailUpdateHandler(DetailForm_ButtonClicked);
            FrmDetails.Show();
        }

        private void DetailForm_ButtonClicked(object sender, DetailUpdateEventArgs e)
        {
            dataGridView.ColumnCount = 8;
            dataGridView.Columns[0].Name = "NAME";
            dataGridView.Columns[1].Name = "NRIC";
            dataGridView.Columns[2].Name = "DATE";
            dataGridView.Columns[3].Name = "COMPANY";
            dataGridView.Columns[4].Name = "TELEPHONE";
            dataGridView.Columns[5].Name = "CONTACT PERSON";
            dataGridView.Columns[6].Name = "PURPOSE";
            dataGridView.Columns[7].Name = "ITEM";
        }
       
    }
}

//frmdetails

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

namespace Test
{
    public partial class FrmDetails : Form
    {
        public delegate void DetailUpdateHandler(object sender, DetailUpdateEventArgs e);

        public event DetailUpdateHandler DetailUpdated;

        public FrmDetails()
        {
            InitializeComponent();
        }

        private void btnOK_Click(object sender, EventArgs e)
        {
            string sNewName = txtName.Text;
            string sNewNRIC = txtNRIC.Text;
            string sNewDate = txtDate.Text;
            string sNewCompany = txtCompany.Text;
            string sNewTel = txtTel.Text;
            string sNewContact = txtContact.Text;

            DetailUpdateEventArgs args = new DetailUpdateEventArgs(sNewName,
                sNewNRIC, sNewDate, sNewCompany, sNewTel, sNewContact);

            DetailUpdated(this, args);



            this.Dispose();
        }

        private void btnCancel_Click(object sender, EventArgs e)
        {
            this.Dispose();
        }
    }

    public class DetailUpdateEventArgs : System.EventArgs
    {
        private string mNewName;
        private string mNewNRIC;
        private string mNewDate;
        private string mNewCompany;
        private string mNewTel;
        private string mNewContact;

        public DetailUpdateEventArgs(string sNewName, string sNewNRIC,
            string sNewDate, string sNewCompany, string sNewTel,
            string sNewContact)
        {
            this.mNewName = sNewName;
            this.mNewNRIC = sNewNRIC;
            this.mNewDate = sNewDate;
            this.mNewCompany = sNewCompany;
            this.mNewTel = sNewTel;
            this.mNewContact = sNewContact;
        }

        public string Name
        {
            get
            {
                return mNewName;
            }
        }

        public string NRIC
        {
            get
            {
                return mNewNRIC;
            }
        }

        public string Date
        {
            get
            {
                return mNewDate;
            }
        }

        public string Company
        {
            get
            {
                return mNewCompany;
            }
        }

        public string Tel
        {
            get
            {
                return mNewTel;
            }
        }

        public string Contact
        {
            get
            {
                return mNewContact;
            }
        }
    }
}