C# WinForm的习题

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 Ch12Ex04
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        /// <summary>
        /// 点击button按钮触发事件
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void button1_Click(object sender, EventArgs e)
        {
            string RadioButton = null;
            string CheckBoxs = new string('\0', 0);
            if (radioButton1.Checked)
            {
                RadioButton = radioButton1.Text;
            }
            if (radioButton2.Checked)
            {
                RadioButton = radioButton2.Text;
            }
            if (radioButton3.Checked)
            {
                RadioButton = radioButton3.Text;
            }
            if (checkBox1.Checked)
            {
                CheckBoxs += checkBox1.Text + " ";
            }
            if (checkBox2.Checked)
            {
                CheckBoxs += checkBox2.Text + " ";
            }
            if (checkBox3.Checked)
            {
                CheckBoxs += checkBox3.Text + " ";
            }
            if (CheckBoxs.Length == 0)
            {
                CheckBoxs = "没有复选框被选中";
            }
            else
            {
                CheckBoxs = "复选框  " + CheckBoxs + "  被选中";
            }
            if (RadioButton==null)
            {
                RadioButton = "没有单选框被选中";
            }
            else
            {
                RadioButton = "单选框  " + RadioButton + "  被选中";
            }

            MessageBox.Show(RadioButton + Environment.NewLine + Environment.NewLine + CheckBoxs);
            this.Close();
        }
        /// <summary>
        /// trackBar1_Scroll方法是用来控制text文本的大小的
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void trackBar1_Scroll(object sender, EventArgs e)
        {
            //文本字体
            FontFamily oldFontFamily = this.label1.Font.FontFamily;
            //样式
            FontStyle oldFontStyle = this.label1.Font.Style;
            //获得滚动条当前的值
            float fontSize = this.trackBar1.Value;
            Font newFont = new Font(oldFontFamily, fontSize, oldFontStyle);
            this.label1.Font = newFont;
        }
    }
}