C#父窗体获取子窗体参数

父窗体：

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;

namespace NCFileReadAndDisplay
{
    public partial class Form1 : Form
    {
        string ncInfo="";
        public Form1()
        {
            InitializeComponent();
        }
        public string nc_format_info
        {
            get { return this.ncInfo; }
            set { this.ncInfo = value; }
        }
        private void toolStripLabel1_Click(object sender, EventArgs e)//NC文件读取
        {
            NCFormatInfo ncfi = new NCFormatInfo();
            ncfi.Owner = this;
            ncfi.ShowDialog();
            MessageBox.Show(ncInfo);
        }
    }
}

子窗体：

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;

namespace NCFileReadAndDisplay
{
    public partial class NCFormatInfo : Form
    {
        public NCFormatInfo()
        {
            InitializeComponent();
        }

        private void button1_Click(object sender, EventArgs e)
        {
            Form1 form = (Form1)this.Owner;
            form.nc_format_info = textBox1.Text + "," + textBox2.Text + "," + textBox3.Text;
            this.Close();
        }
    }
}