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;
using System.IO;
namespace WindowsFormsApplication4
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }
        
 
//時間按鈕點擊事件
        private void 時間日期ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            textBox1.Text = DateTime.Now.ToString("HH:mm yyyy/MM/dd");
        }
        //撤銷按鈕點擊事件
        private void 撤消UToolStripMenuItem_Click(object sender, EventArgs e)
        {
            textBox1.Undo();
        }
        
 
//剪切按鈕事件
        private void 剪切TToolStripMenuItem_Click(object sender, EventArgs e)
        {
            textBox1.Cut();
        }
        //復制按鈕事件
        private void 復制CToolStripMenuItem_Click(object sender, EventArgs e)
        {
            textBox1.Copy();
        }
        //粘貼按鈕事件
        private
 
 void 粘貼PToolStripMenuItem_Click(object sender, EventArgs e)
        {
            textBox1.Paste();
        }
        //刪除按鈕事件
        private void toolStripMenuItem3_Click(object sender, EventArgs e)
        {
            textBox1.SelectedText = "";
        }
        //全選按鈕事件
        private void 全選AToolStripMenuItem_Click(object sender, EventArgs e)
        {
            textBox1.SelectAll();
        }
        //查找按鈕事件
        private void toolStripMenuItem1_Click(object sender, EventArgs e)
        {
            Form2 f2 = new Form2(this);
            f2.Owner = this;
            f2.Show();
        }
        //替換按鈕點擊事件
        private void 替換ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            Form3 f3 = new Form3(this);
            f3.Owner = this;
            f3.Show();
        }
        //換行按鈕點擊事件
        private void 自動換行ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            if (textBox1.WordWrap)
            {
                textBox1.WordWrap = false;
                textBox1.ScrollBars = ScrollBars.Both;
            }
            else
            {
                textBox1.WordWrap = true;
                textBox1.ScrollBars = ScrollBars.Vertical;
            }
        }
        //字體按鈕點擊事件
        private void 字體ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            DialogResult dll = fontDialog1.ShowDialog();
            if (dll == DialogResult.OK)
            {
                textBox1.Font = fontDialog1.Font;
            }
        }
        //顏色按鈕點擊事件
        private void 字體ToolStripMenuItem1_Click(object sender, EventArgs e)
        {
            DialogResult dll = colorDialog1.ShowDialog();
            if (dll == DialogResult.OK)
            {
                textBox1.ForeColor = colorDialog1.Color;
            }
        }
        //打開按鈕點擊事件
        private void 打開OToolStripMenuItem_Click(object sender, EventArgs e)
        {
            openFileDialog1.Filter = "文本文件|*.txt";//選擇文件能打開格式,多個"文本文件|*.txt|文本文檔|*.doc|所有文件|*.*"
            DialogResult dll = openFileDialog1.ShowDialog();
            if (dll == DialogResult.OK)
            {                                     //打開文件路徑,以文件的默認編碼方式打開
                StreamReader sr = new StreamReader(openFileDialog1.FileName, Encoding.Default);
                textBox1.Text = sr.ReadToEnd();
            }
        }
        string save = "";
        private void 保存SToolStripMenuItem_Click(object sender, EventArgs e)
        {
            if (save == "")//判斷有沒有保存路徑
            {
                DialogResult dll = saveFileDialog1.ShowDialog();
                if (dll == DialogResult.OK)
                {
                    StreamWriter sw = new StreamWriter(saveFileDialog1.FileName);
                    sw.Write(textBox1.Text);
                    sw.Flush();
                    save = saveFileDialog1.FileName;
                    sw.Close();
                }
            }
            else
            {
                StreamWriter sw = new StreamWriter(saveFileDialog1.FileName);
                sw.Write(textBox1.Text);
                sw.Flush();
                sw.Close();
            }
        }
        //底部菜單欄
        private void textBox1_TextChanged(object sender, EventArgs e)
        {
            toolStripLabel1.Text = "字數:" + textBox1.TextLength;
            toolStripLabel2.Text = "行數" + (textBox1.GetLineFromCharIndex(textBox1.TextLength)+1);
        }

    }
}

form1

Form1

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 WindowsFormsApplication4
{
    public partial class Form2 : Form
    {
        Form1 F1 = null;
        public Form2(Form1 f1)
        {
            InitializeComponent();
            F1 = f1;
        }
        int z = 0;
        private void button1_Click(object sender, EventArgs e)
        {
            string s = F1.textBox1.Text;
            if (z < 0)
            {
                z = 0;
            }
            z = s.IndexOf(textBox1.Text, z);
            if (z >= 0)
            {

                F1.textBox1.Select(z, textBox1.TextLength);
                F1.Focus();
                z++;
            }
            else
            {
                MessageBox.Show("找不到" + "\"" + textBox1.Text + "\"");
            }
        }
    }
}

form2

Form2

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 WindowsFormsApplication4
{
    public partial class Form3 : Form
    {
        Form1 F1 = null;
        public Form3(Form1 f1)
        {
            InitializeComponent();
            F1 = f1;
        }

        private void button1_Click(object sender, EventArgs e)
        {
            int z = 0;
            string s = F1.textBox1.Text;
            if (s.IndexOf(textBox1.Text, z) < 0)
            {
                MessageBox.Show("找不到" + "\"" + textBox1.Text + "\"");
            }
            for (; ; )
            {
                if (z < 0)
                {
                    F1.Focus();
                    break;
                }
                z = s.IndexOf(textBox1.Text, z);
                if (z >= 0)
                {
                    F1.textBox1.Select(z, textBox1.TextLength);
                    F1.textBox1.SelectedText = textBox2.Text;
                    z++;
                }
            }
        }
    }
}

form3

Form3

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