简易记事本

 public partial class Form2 : Form
    {
        public Form2()
        {
            InitializeComponent();
        }
        private Form1 jishiben;
        public Form2(Form1 f)
        {
            InitializeComponent();
            jishiben = f;
        }
        public int index = -1;
        private void cha_Click(object sender, EventArgs e)
        {
            string mubiao = txtchazhao.Text;
            string yuanshuju = jishiben.txtjishiben.Text;
             index = yuanshuju.IndexOf(mubiao,index+1);
             if (index > -1)
             {
                 jishiben.txtjishiben.Select(index, mubiao.Length);
                 jishiben.Focus();
             }
        }

        private void tihuan_Click(object sender, EventArgs e)
        {
            jishiben.txtjishiben.Text = jishiben.txtjishiben.Text.Replace(txtchazhao.Text,txttihuan.Text);
        }
    }

public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void 打开OToolStripMenuItem_Click(object sender, EventArgs e)
        {
            openFileDialog1.Filter = "文本文档|*.txt|所有文件|*.*";
            DialogResult isok = openFileDialog1.ShowDialog();
            if (isok == DialogResult.OK)
            {
                string filePath = openFileDialog1.FileName;
                this.txtjishiben.Text = File.ReadAllText(filePath, Encoding.Default);
                this.Text = new FileInfo(filePath).Name;//获取文件名
            }
        }

        private void 新建NToolStripMenuItem_Click(object sender, EventArgs e)
        {
            this.txtjishiben.Text="";
        }

        private void 另存为AToolStripMenuItem_Click(object sender, EventArgs e)
        {
            saveFileDialog1.Filter = "文本文档|*.txt|所有文件|*.*";
            DialogResult isok = saveFileDialog1.ShowDialog();
            if (isok == DialogResult.OK)
            {
                string filename = saveFileDialog1.FileName;
                //StreamWriter sw = new StreamWriter(filename);
                //sw.Write(this.txtjishiben.Text);
                //sw.Close();
                File.WriteAllText(filename,this.txtjishiben.Text,Encoding.Default);
            }
        }

        private void 保存SToolStripMenuItem_Click(object sender, EventArgs e)
        {
            string path = openFileDialog1.FileName;
            string n = this.txtjishiben.Text;
            File.WriteAllText(path, n,Encoding.Default);
        }

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

        private void 打印PToolStripMenuItem_Click(object sender, EventArgs e)
        {
            printDialog1.Document = printDocument1;
            DialogResult isok = printDialog1.ShowDialog();
            if (isok == DialogResult.OK)
            {
                printDocument1.Print();
            }
        }

        private void 打印预览VToolStripMenuItem_Click(object sender, EventArgs e)
        {
            printPreviewDialog1.ShowDialog();
            printPreviewDialog1.Document = printDocument1;
        }

        private void printDocument1_PrintPage(object sender, System.Drawing.Printing.PrintPageEventArgs e)
        {
            System.Drawing.Font f=new System.Drawing.Font("隶书",19.8f);
            e.Graphics.DrawString(this.txtjishiben.Text,f,System.Drawing.Brushes.Blue,new Point(100,100)); ;
        }

        private void 查找ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            Form2 f = new Form2(this);
            f.Show();
        }

    }