c#只有空白窗体没有内容

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 WindowsFormsApplication2
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{

        richTextBox1.AppendText("计算机名:" + SystemInformation.ComputerName);            
        richTextBox1.AppendText(Environment.NewLine);//换行
        richTextBox1.AppendText("计算机名:" + Environment.MachineName);
        richTextBox1.AppendText(Environment.NewLine);
        richTextBox1.AppendText("操作系统:" + Environment.OSVersion.Platform);
        richTextBox1.AppendText(Environment.NewLine);
        richTextBox1.AppendText("版本号:" + Environment.OSVersion.VersionString);
        richTextBox1.AppendText(Environment.NewLine);
        richTextBox1.AppendText("处理器个数:" + Environment.ProcessorCount);
        richTextBox1.AppendText(Environment.NewLine);
        //判断操作系统位数
        if (Environment.Is64BitOperatingSystem)
        {
            richTextBox1.AppendText("操作系统位数:64bit.");
        }
        else
        {
            richTextBox1.AppendText("操作系统位数:32bit.");
        }
        richTextBox1.AppendText (Environment.NewLine );
        //判断网络是否连接
        if (SystemInformation.Network)
        {
            richTextBox1.AppendText("网络连接:已连接");
        }
        else
        {
            richTextBox1.AppendText("网络连接:未连接");
        }
        richTextBox1.AppendText(Environment.NewLine);
        //判断启动模式
        if (SystemInformation.BootMode.ToString() == "Normal")
            richTextBox1.AppendText("启动模式:正常启动");
        if (SystemInformation.BootMode.ToString() == "FailSafe")
            richTextBox1.AppendText("启动模式:安全启动");
        if (SystemInformation.BootMode.ToString() == "FailSafeWithNework")
            richTextBox1.AppendText("启动方式:通过网络服务启动");
        richTextBox1.AppendText(Environment.NewLine);
        richTextBox1.AppendText("显示器数量:" + SystemInformation.MonitorCount);
        richTextBox1.AppendText(Environment.NewLine);
        richTextBox1.AppendText("显示器分辨率:" + SystemInformation.PrimaryMonitorMaximizedWindowSize.Width + " x " + SystemInformation.PrimaryMonitorMaximizedWindowSize.Height);
        richTextBox1.AppendText(Environment.NewLine);
        richTextBox1.AppendText("主显示器当前分辨率:" +SystemInformation.PrimaryMonitorSize.Width + " x " + SystemInformation.PrimaryMonitorSize.Height);
        richTextBox1.AppendText(Environment.NewLine);
        richTextBox1.AppendText("鼠标按钮个数:"+SystemInformation.MouseButtons.ToString());//不知道怎么获取出来的是5个按钮
        richTextBox1.AppendText(Environment.NewLine);
        richTextBox1.AppendText("系统限定目录:" +Environment.SystemDirectory);
        richTextBox1.AppendText(Environment.NewLine);
        richTextBox1.AppendText("系统内存:"+Environment.SystemPageSize.ToString());
        richTextBox1.AppendText(Environment.NewLine);            
    }
}

}