Windows实验四总结（记事本）

 

  实验四真的是自己做的最墨迹的一次实验了，要求是做一个类似记事本，但功能不要求全部实现。

  这是一张系统自带记事本的图

这是自己做出来的

这是自己做出来的记事本的图

  实现的功能：1.文件部分：打开文件，保存文件，关闭文件（我查到用RichTextBox保存另存为啥的都一句话的事，但当时快交作业了懒得改了，没做另存为文件，后期再改进吧）

                         2.操作功能：剪切，复制，粘贴，查找，替换，加下划线，加粗，文字变斜体，更改字号，更改颜色，靠左对齐，居中对齐，靠右对齐，全选

1.打开文件

        private void MOpen_Click(object sender, EventArgs e)
        {
            //这个按钮是用来打开文件的
            DialogResult ans;
            openFileDialog1.Filter = "所有*txt文件|*.txt";//筛选只要txt文件
            openFileDialog1.InitialDirectory = "D://";//初始化打开路径
            ans = openFileDialog1.ShowDialog();//打开文件

            if (ans == DialogResult.OK)//如果用户点击了OK，就一个一个字节的将文本读入
            {
                richTextBox1.Text = " ";
                fn = openFileDialog1.FileName;
                FileStream fs = new FileStream(fn, FileMode.Open, FileAccess.ReadWrite);
                long n = fs.Length;
                byte[] b = new byte[n];
                for (int i = 0; i < n; i++)//按字节读入
                {
                    b[i] = Convert.ToByte(fs.ReadByte());
                }
                richTextBox1.Text = Encoding.Default.GetString(b);
                fs.Close();
            }
        }

①要创建一个openFileDialog，注意这个组件的过滤器功能（Filter）和初始化功能（InitialDirectory）

②要注意窗口打开后的那个写法，就背下来就好if(ans=DialogResult.OK)

③文件流部分分三步，创建流，读/写文件，关闭流，缺一不可

④为了解决中文乱码问题需要转码，这个和java里用RandomAccessFile流是一个道理，这个也背下来就行

⑤c#里类型转换用的是Convert.

2.保存文件

 private void MSave_Click(object sender, EventArgs e)
        {
            //这个按钮是用来保存文件的
            if (fn == null)
                MessageBox.Show("请先打开文件");
            else
            {
                FileStream fs = new FileStream(fn, FileMode.Open, FileAccess.Write);
                byte[] b = Encoding.Default.GetBytes(richTextBox1.Text);//把字符串编成字节
                for (int i = 0; i < b.Length; i++)
                    fs.WriteByte(b[i]);
                fs.Close();
            }
        }

逻辑：要想保存文件首先要有已经打开的文件，要是没有已经打开的文件要用MessageBox.Show来提示，然后创建写文件流来将文件写回去，这里也涉及到转码的问题，将文件内容转换到字节数组里，再一个一个字节的写回文件。最后关闭流。

3.退出按钮

  private void MExit_Click(object sender, EventArgs e)
        {
            //这是退出按钮
            //
            this.Close();
        }

 

直接将当前的窗口关闭了。

4.查找

private void MFind_Click(object sender, EventArgs e)
        {
            Form2 fr = new Form2(richTextBox1);
            fr.ShowDialog();
        }

 public partial class Form2 : Form
    {
        private RichTextBox richTextBox2;
        public Form2()
        {
            InitializeComponent();
        }
        public Form2(RichTextBox richTextBox1)
        {
            InitializeComponent();
            richTextBox2 = richTextBox1;
        }

        private void Form2_Load(object sender, EventArgs e)
        {

        }
        int start = 0;
        int search = 0;//查询的个数
        private void Button1_Click(object sender, EventArgs e)
        {
            int pos = richTextBox2.Text.IndexOf(textFind.Text,start);
            DialogResult ans;
            if (pos != -1)
            {
                richTextBox2.SelectionStart = pos;
                richTextBox2.SelectionLength = textFind.Text.Length;
                search++;
                start = pos + textFind.Text.Length;
            }
            else
            {
                if(search==0)
                {
                    ans=MessageBox.Show("没有查找到！");
                }
                else
                {
                    ans=MessageBox.Show("已经查找到末尾！");
                    start = 0;
                    search = 0;
                    Focus();
                }
            }
        }

        private void Button2_Click(object sender, EventArgs e)
        {
            this.Close();
        }
    }

①窗口跳转：首先要新建一个Form2,然后在Form1里面的按钮Click事件里创建一个Form2对象，把想传过去的参数传过去，然后显示Form2，在Form2里要新建一个你跟你传过来的参数一样的组件（比如这里传的是RichTextBox），然后新建一个初始化函数，把新组件和旧组件的内容弄一样了就可以了。

②查找，主要就是三个函数IndexOf,SelectionStart,SelectionLength,注意在那个Form1里要把HideSelection那个属性改成false,要不然你查找到的东西不会底色变蓝！(这个改了好久问同学才知道，老师明明讲过都怪自己不好好记笔记)

5.替换（替换的本质和查找差不多，找到了就换了呗）

   private void MReplace_Click(object sender, EventArgs e)
        {
            Form3 fr = new Form3(richTextBox1);
            fr.ShowDialog();
        }

 private RichTextBox richTextBox3;//新建一个该类中的要操作的对象
        public Form3()//Form3的无参构造函数
        {
            InitializeComponent();
        }
        public Form3(RichTextBox richTextBox1)//Form3的有参构造函数，将第一个界面中的文本框作为参数传进来
        {
            InitializeComponent();
            richTextBox3 = richTextBox1;
        }

        private void Button4_Click(object sender, EventArgs e)
        {
            this.Close();
        }
        int start = 0;
        int search = 0;
        private void Button1_Click(object sender, EventArgs e)
        {
            int pos = richTextBox3.Text.IndexOf(textBox1.Text,start);//从起始位置开始搜索
            DialogResult ans;
            if (pos != -1)
            {
                richTextBox3.SelectionStart = pos;
                richTextBox3.SelectionLength = textBox1.Text.Length;
                search++;
                start = pos + textBox1.Text.Length;
            }
            else
            {
                if (search == 0)
                {
                    ans = MessageBox.Show("没有查找到！");
                }
                else
                {
                    if (search == 0)
                    {
                        ans = MessageBox.Show("没有查找到！");

                    }
                    else
                    {
                        ans = MessageBox.Show(string.Format("已经查找到末尾！共找到{0}个结果", search), "查找结果", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                        if (ans == DialogResult.Yes)
                        {
                            search = 0;
                            start = 0;
                            Focus();
                        }
                    }
                    
                }
            }
        }
        int start2 = 0;
        private void Button2_Click(object sender, EventArgs e)
        {
            //这是替换按钮功能的实现
            int pos = richTextBox3.Text.IndexOf(textBox2.Text, start2);
            richTextBox3.SelectedText=textBox2.Text;
            start2 = pos + textBox2.Text.Length;
        }
        int start1 = 0;
        private void Button3_Click(object sender, EventArgs e)
        {
            //这是全部替换按钮功能的实现
            int pos = richTextBox3.Text.IndexOf(textBox1.Text, start1);//从起始位置开始搜索
            if (pos != -1)
            {
                richTextBox3.SelectionStart = pos;
                richTextBox3.SelectionLength = textBox1.Text.Length;
                search++;
                start1 = pos + textBox1.Text.Length;
                richTextBox3.Text = richTextBox3.Text.Replace(richTextBox3.SelectedText, textBox2.Text);
            }

        }
    }

6.布局组件：最上面一栏叫MenuStrip,它下面那栏叫toolStrip

7.一种奇妙的颜色盘叫colorDialog

8.剩下的复制剪切粘贴就一句话的事，把函数记清。

完整代码如下

Form1.cs

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;
using System.IO;


namespace win_lib4_new
{
    public partial class Form1 : Form
    {




















        private string fn;
        public Form1()
        {
            InitializeComponent();
        }

        private void ToolStripComboBox1_Click(object sender, EventArgs e)
        {

        }

        private void 查看VToolStripMenuItem_Click(object sender, EventArgs e)
        {

        }
              
        /*-----------文件按钮：打开保存文件，退出-----------*/
        private void MOpen_Click(object sender, EventArgs e)
        {
            //这个按钮是用来打开文件的
            DialogResult ans;
            openFileDialog1.Filter = "所有*txt文件|*.txt";//筛选只要txt文件
            openFileDialog1.InitialDirectory = "D://";//初始化打开路径
            ans = openFileDialog1.ShowDialog();//打开文件

            if (ans == DialogResult.OK)//如果用户点击了OK，就一个一个字节的将文本读入
            {
                richTextBox1.Text = " ";
                fn = openFileDialog1.FileName;
                FileStream fs = new FileStream(fn, FileMode.Open, FileAccess.ReadWrite);
                long n = fs.Length;
                byte[] b = new byte[n];
                for (int i = 0; i < n; i++)//按字节读入
                {
                    b[i] = Convert.ToByte(fs.ReadByte());
                }
                richTextBox1.Text = Encoding.Default.GetString(b);
                fs.Close();
            }
        }

        private void MOpen_2_Click(object sender, EventArgs e)
        {
            //这个按钮是用来打开文件的，和上一个按钮一样
            DialogResult ans;
            ans = openFileDialog1.ShowDialog();//打开文件
            openFileDialog1.Filter = "所有*txt文件|*.txt";//筛选只要txt文件
            openFileDialog1.InitialDirectory = "D://";//初始化打开路径
            if (ans == DialogResult.OK)//如果用户点击了OK，就一个一个字节的将文本读入
            {
                richTextBox1.Text = " ";
                fn = openFileDialog1.FileName;
                FileStream fs = new FileStream(fn, FileMode.Open, FileAccess.ReadWrite);
                long n = fs.Length;
                byte[] b = new byte[n];
                for (int i = 0; i < n; i++)//按字节读入
                {
                    b[i] = Convert.ToByte(fs.ReadByte());
                }
                richTextBox1.Text = Encoding.Default.GetString(b);
                fs.Close();
            }
        }

        private void MSave_Click(object sender, EventArgs e)
        {
            //这个按钮是用来保存文件的
            if (fn == null)
                MessageBox.Show("请先打开文件");
            else
            {
                FileStream fs = new FileStream(fn, FileMode.Open, FileAccess.Write);
                byte[] b = Encoding.Default.GetBytes(richTextBox1.Text);//把字符串编成字节
                for (int i = 0; i < b.Length; i++)
                    fs.WriteByte(b[i]);
                fs.Close();
            }
        }
        private void MSave_2_Click(object sender, EventArgs e)
        {
            //这个按钮是用来保存文件的，和上一个按钮一样
            if (fn == null)
                MessageBox.Show("请先打开文件");
            else
            {
                FileStream fs = new FileStream(fn, FileMode.Open, FileAccess.Write);
                byte[] b = Encoding.Default.GetBytes(richTextBox1.Text);//把字符串编成字节
                for (int i = 0; i < b.Length; i++)
                {
                    fs.WriteByte(b[i]);
                }
                fs.Close();
            }
        }


        private void MCut_2_Click(object sender, EventArgs e)
        {
            //这是剪切按钮
            richTextBox1.Cut();
        }

        private void MCopy_2_Click(object sender, EventArgs e)
        {
            //这是复制按钮
            richTextBox1.Copy();
        }

        private void MPaste_2_Click(object sender, EventArgs e)
        {
            //这是黏贴按钮
            richTextBox1.Paste();
        }

        private void MExit_Click(object sender, EventArgs e)
        {
            //这是退出按钮
            //
            this.Close();
        }

        private void MCut_Click(object sender, EventArgs e)
        {
            richTextBox1.Cut();
        }

        private void MCopy_Click(object sender, EventArgs e)
        {
            richTextBox1.Copy();
        }

        private void MPaste_Click(object sender, EventArgs e)
        {
            richTextBox1.Paste();
        }

        private void MFont_Click(object sender, EventArgs e)
        {

        }

        private void ToolStripMenuItem3_Click(object sender, EventArgs e)
        {
            //这是黑色菜单项对应的Click事件
            richTextBox1.SelectionColor = Color.Black;
            MBlack.Checked = true;
            MMoreColor.Checked = false;
            MRed.Checked = false;
            MBlue.Checked = false;
            MGreen.Checked = false;
            MYellow.Checked = false;

        }
        bool un = false;
        private void MUnderline_Click(object sender, EventArgs e)
        {
            //这个按钮是用来将字体加上下划线的
            if (un == false)
            {
                richTextBox1.SelectionFont = new Font(this.Font.Name, this.Font.Size, FontStyle.Underline);
                un = true;
            }
            else
            {
                richTextBox1.SelectionFont = new Font(this.Font.Name, this.Font.Size, FontStyle.Regular);
                un = false;
            }
        }
        bool it = false;
        private void MItalic_Click(object sender, EventArgs e)
        {
            //这个按钮是用来将字体变成斜体的
            if (it == false)
            {
                richTextBox1.SelectionFont = new Font(this.Font.Name, this.Font.Size, FontStyle.Italic);
                it = true;
            }
            else
            {
                richTextBox1.SelectionFont = new Font(this.Font.Name, this.Font.Size, FontStyle.Regular);
                it = false;
            }
        }
        bool ov = false;
        private void MOverstriking_Click(object sender, EventArgs e)
        {
            //这个按钮是用来将字体加粗的
            if (ov == false)
            {
                richTextBox1.SelectionFont = new Font(this.Font.Name, this.Font.Size, FontStyle.Bold);
                ov = true;
            }
            else
            {
                richTextBox1.SelectionFont = new Font(this.Font.Name, this.Font.Size, FontStyle.Regular);
                ov = false;
            }
        }

        private void 黑体ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            //黑体菜单项对应的Click事件
            richTextBox1.SelectionFont = new Font("黑体", richTextBox1.Font.Size);
            MHei.Checked = true;
            MSong.Checked = false;
            MKai.Checked = false;
            MLi.Checked = false;
        }

        private void MSong_Click(object sender, EventArgs e)
        {
            //宋体菜单项对应的Click事件
            richTextBox1.SelectionFont = new Font("宋体", richTextBox1.Font.Size);
            MSong.Checked = true;
            MHei.Checked = false;
            MKai.Checked = false;
            MLi.Checked = false;
        }

        private void MKai_Click(object sender, EventArgs e)
        {
            //楷书菜单项对应的Click事件
            richTextBox1.SelectionFont = new Font("楷书", richTextBox1.Font.Size);
            MKai.Checked = true;
            MHei.Checked = false;
            MSong.Checked = false;
            MLi.Checked = false;
        }

        private void MLi_Click(object sender, EventArgs e)
        {
            //隶书菜单项对应的Click事件
            richTextBox1.SelectionFont = new Font("隶书", richTextBox1.Font.Size);
            MLi.Checked = true;
            MHei.Checked = false;
            MKai.Checked = false;
            MSong.Checked = false;
        }

        private void 更多颜色选择ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            DialogResult ans;
            ans = colorDialog1.ShowDialog();
            if (ans == DialogResult.OK)
            {
                richTextBox1.SelectionColor = colorDialog1.Color;
            }
            MMoreColor.Checked = true;
            MBlack.Checked = false;
            MRed.Checked = false;
            MBlue.Checked = false;
            MGreen.Checked = false;
            MYellow.Checked = false;
        }


        private void MFind_Click(object sender, EventArgs e)
        {
            Form2 fr = new Form2(richTextBox1);
            fr.ShowDialog();
        }

        private void MFile_Click(object sender, EventArgs e)
        {

        }

        private void 帮助HToolStripMenuItem_Click(object sender, EventArgs e)
        {

        }

        private void MReplace_Click(object sender, EventArgs e)
        {
            Form3 fr = new Form3(richTextBox1);
            fr.ShowDialog();
        }

        private void MRed_Click(object sender, EventArgs e)
        {
            //这是红色菜单项对应的Click事件
            richTextBox1.SelectionColor = Color.Red;
            MRed.Checked = true;
            MBlack.Checked = false;
            MMoreColor.Checked = false;
            MBlue.Checked = false;
            MGreen.Checked = false;
            MYellow.Checked = false;
        }

        private void MBlue_Click(object sender, EventArgs e)
        {
            //这是蓝色菜单项对应的Click事件
            richTextBox1.SelectionColor = Color.Blue;
            MBlue.Checked = true;
            MRed.Checked = false;
            MBlack.Checked = false;
            MMoreColor.Checked = false;
            MGreen.Checked = false;
            MYellow.Checked = false;
        }

        private void MGreen_Click(object sender, EventArgs e)
        {
            //这是绿色菜单项对应的Click事件
            richTextBox1.SelectionColor = Color.Green;
            MGreen.Checked = true;
            MRed.Checked = false;
            MBlack.Checked = false;
            MMoreColor.Checked = false;
            MBlue.Checked = false;
            MYellow.Checked = false;
        }

        private void MYellow_Click(object sender, EventArgs e)
        {
            //这是黄色菜单项对应的Click事件
            richTextBox1.SelectionColor = Color.Yellow;
            MYellow.Checked = true;
            MRed.Checked = false;
            MBlack.Checked = false;
            MMoreColor.Checked = false;
            MBlue.Checked = false;
            MGreen.Checked = false;

        }

        private void ToolStripComboBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (toolStripComboBox1.Text == "6")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 6) ;
            else if (toolStripComboBox1.Text == "7")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 7);
            else if (toolStripComboBox1.Text == "8")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 8);
            else if (toolStripComboBox1.Text == "9")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 9);
            else if (toolStripComboBox1.Text == "10")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 10);
            else if (toolStripComboBox1.Text == "11")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 11);
            else if (toolStripComboBox1.Text == "12")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 12);
            else if (toolStripComboBox1.Text == "13")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 13);
            else if (toolStripComboBox1.Text == "14")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 14);
            else if (toolStripComboBox1.Text == "15")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 15);
            else if (toolStripComboBox1.Text == "16")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 16);
            else if (toolStripComboBox1.Text == "17")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 17);
            else if (toolStripComboBox1.Text == "18")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 18);
            else if (toolStripComboBox1.Text == "19")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 19);
            else if (toolStripComboBox1.Text == "20")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 20);
            else if (toolStripComboBox1.Text == "21")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 21);
            else if (toolStripComboBox1.Text == "22")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 22);
            else if (toolStripComboBox1.Text == "23")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 23);
            else if (toolStripComboBox1.Text == "24")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 24);
            else if (toolStripComboBox1.Text == "25")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 25);
            else if (toolStripComboBox1.Text == "26")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 26);
            else if (toolStripComboBox1.Text == "27")
                richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 27);
        }

        private void ToolStripComboBox2_SelectedIndexChanged(object sender, EventArgs e)
        {
            if (toolStripComboBox2.Text == "红色")
                richTextBox1.SelectionColor = Color.Red;
            else if (toolStripComboBox2.Text == "绿色")
                richTextBox1.SelectionColor = Color.Green;
            else if (toolStripComboBox2.Text == "黑色")
                richTextBox1.SelectionColor = Color.Black;
            else if (toolStripComboBox2.Text == "蓝色")
                richTextBox1.SelectionColor = Color.Blue;
            else if (toolStripComboBox2.Text == "黄色")
                richTextBox1.SelectionColor = Color.Yellow;
            else if (toolStripComboBox2.Text == "更多颜色选择")
            {
                DialogResult ans;
                ans = colorDialog1.ShowDialog();
                if (ans == DialogResult.OK)
                {
                    richTextBox1.SelectionColor = colorDialog1.Color;
                }
            }
        }

        private void 小6磅ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            //这是小菜单项对应的Click事件
            richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 6);
            MSmall.Checked = true;
            MMiddle.Checked = false;
            MBig.Checked = false;
            MSuperBig.Checked = false;
  
        }

        private void 中12磅ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            //这是中菜单项对应的Click事件
            richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 12);
            MMiddle.Checked = true;
            MSmall.Checked = false;         
            MBig.Checked = false;
            MSuperBig.Checked = false;
        }

        private void 大18磅ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            //这是菜单项对应的Click事件
            richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 18);
            MBig.Checked = true;
            MSmall.Checked = false;
            MMiddle.Checked = false;           
            MSuperBig.Checked = false;
        }

        private void 超大24磅ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            //这是超大菜单项对应的Click事件
            richTextBox1.SelectionFont = new Font(richTextBox1.Font.FontFamily, 24);
            MSuperBig.Checked = true;
            MSmall.Checked = false;
            MMiddle.Checked = false;
            MBig.Checked = false;
        }
      //设置界面属性
        private void setpos()
        {
            richTextBox1.Left = 0;
            richTextBox1.Top = toolStrip1.Height + menuStrip1.Height;
            richTextBox1.Width = this.ClientSize.Width;
            richTextBox1.Height = this.ClientSize.Height - menuStrip1.Height - toolStrip1.Height;
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            setpos();
        }

        private void Form1_Resize(object sender, EventArgs e)
        {
            setpos();
        }

        private void ToolStripButton1_Click(object sender, EventArgs e)
        {
            //全选按钮
            richTextBox1.SelectAll();
        }

        private void MLeft_Click(object sender, EventArgs e)
        {
            richTextBox1.SelectionAlignment = HorizontalAlignment.Left;
        }

        private void MCenter_Click(object sender, EventArgs e)
        {
            richTextBox1.SelectionAlignment = HorizontalAlignment.Center;
        }

        private void MRight_Click(object sender, EventArgs e)
        {
            richTextBox1.SelectionAlignment = HorizontalAlignment.Right;
        }
    }
}

Form1视图

Form2.cs

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 win_lib4_new
{
    public partial class Form2 : Form
    {
        private RichTextBox richTextBox2;
        public Form2()
        {
            InitializeComponent();
        }
        public Form2(RichTextBox richTextBox1)
        {
            InitializeComponent();
            richTextBox2 = richTextBox1;
        }

        private void Form2_Load(object sender, EventArgs e)
        {

        }
        int start = 0;
        int search = 0;//查询的个数
        private void Button1_Click(object sender, EventArgs e)
        {
            int pos = richTextBox2.Text.IndexOf(textFind.Text,start);
            DialogResult ans;
            if (pos != -1)
            {
                richTextBox2.SelectionStart = pos;
                richTextBox2.SelectionLength = textFind.Text.Length;
                search++;
                start = pos + textFind.Text.Length;
            }
            else
            {
                if(search==0)
                {
                    ans=MessageBox.Show("没有查找到！");
                }
                else
                {
                    ans=MessageBox.Show("已经查找到末尾！");
                    start = 0;
                    search = 0;
                    Focus();
                }
            }
        }

        private void Button2_Click(object sender, EventArgs e)
        {
            this.Close();
        }
    }
}

Form2的视图

Form3.cs

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 win_lib4_new
{
    public partial class Form3 : Form
    {
        private RichTextBox richTextBox3;//新建一个该类中的要操作的对象
        public Form3()//Form3的无参构造函数
        {
            InitializeComponent();
        }
        public Form3(RichTextBox richTextBox1)//Form3的有参构造函数，将第一个界面中的文本框作为参数传进来
        {
            InitializeComponent();
            richTextBox3 = richTextBox1;
        }

        private void Button4_Click(object sender, EventArgs e)
        {
            this.Close();
        }
        int start = 0;
        int search = 0;
        private void Button1_Click(object sender, EventArgs e)
        {
            int pos = richTextBox3.Text.IndexOf(textBox1.Text,start);//从起始位置开始搜索
            DialogResult ans;
            if (pos != -1)
            {
                richTextBox3.SelectionStart = pos;
                richTextBox3.SelectionLength = textBox1.Text.Length;
                search++;
                start = pos + textBox1.Text.Length;
            }
            else
            {
                if (search == 0)
                {
                    ans = MessageBox.Show("没有查找到！");
                }
                else
                {
                    if (search == 0)
                    {
                        ans = MessageBox.Show("没有查找到！");

                    }
                    else
                    {
                        ans = MessageBox.Show(string.Format("已经查找到末尾！共找到{0}个结果", search), "查找结果", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                        if (ans == DialogResult.Yes)
                        {
                            search = 0;
                            start = 0;
                            Focus();
                        }
                    }
                    
                }
            }
        }
        int start2 = 0;
        private void Button2_Click(object sender, EventArgs e)
        {
            //这是替换按钮功能的实现
            int pos = richTextBox3.Text.IndexOf(textBox2.Text, start2);
            richTextBox3.SelectedText=textBox2.Text;
            start2 = pos + textBox2.Text.Length;
        }
        int start1 = 0;
        private void Button3_Click(object sender, EventArgs e)
        {
            //这是全部替换按钮功能的实现
            int pos = richTextBox3.Text.IndexOf(textBox1.Text, start1);//从起始位置开始搜索
            if (pos != -1)
            {
                richTextBox3.SelectionStart = pos;
                richTextBox3.SelectionLength = textBox1.Text.Length;
                search++;
                start1 = pos + textBox1.Text.Length;
                richTextBox3.Text = richTextBox3.Text.Replace(richTextBox3.SelectedText, textBox2.Text);
            }

        }
    }
}

Form3视图

另外注意把按钮的ToolTipText记得改了，这样鼠标放上去会显示提示，不改就会很丑。

ps.这个博客纯粹是自己想总结一下当成一个学习笔记用的，写的时候可能没有那么严谨，就是把自己当时的一些思考的过程，总结的东西，放到这里，没想到有人会看。万一有错或者方法比较笨，看到的也麻烦告诉我一下，感谢~（还是觉得根本不会有人看hhh）