winform 保存文件 打开文件 选择文件 字体样式颜色（流 using System.IO;）

 string filePath = "";

         private void 保存SToolStripMenuItem_Click(object sender, EventArgs e)
         {
             if (filePath.Length <= )
             {
                 saveFileDialog1.Filter = "文本文件|*.txt";
                 saveFileDialog1.FileName = "新建文本文件";
                 DialogResult dr = saveFileDialog1.ShowDialog();

                 if (dr == DialogResult.OK)
                 {
                     string path = saveFileDialog1.FileName;
                     StreamWriter sw = new StreamWriter(path);
                     sw.Write(textBox1.Text);
                     sw.Flush();
                     filePath = path;
                 }
             }
             else
             {
                 StreamWriter sw = new StreamWriter(filePath);
                 sw.Write(textBox1.Text);
                 sw.Flush();
             }

         }

保存文件

 private void 打开OToolStripMenuItem_Click(object sender, EventArgs e)
         {
             openFileDialog1.Filter = "文本文件|*.txt|C#代码文件|*.cs|全部文件|*.*";
             DialogResult dr = openFileDialog1.ShowDialog();
             if (dr == DialogResult.OK)
             {
                 string path = openFileDialog1.FileName;

                 StreamReader sr = new StreamReader(path, Encoding.Default);
                 textBox1.Text = sr.ReadToEnd();

                 string[] name = openFileDialog1.FileName.Split('\\');

                 this.Text = name[name.Length - ] + " - 记事本";

             }
         }

打开文件

 private void 选择文件夹ToolStripMenuItem_Click(object sender, EventArgs e)
         {
             DialogResult dr = folderBrowserDialog1.ShowDialog();
             if (dr == DialogResult.OK)
             {
                 textBox1.Text = folderBrowserDialog1.SelectedPath;

             }
         }

选择文件

 private void 字体ToolStripMenuItem_Click(object sender, EventArgs e)
         {
             DialogResult dr = fontDialog1.ShowDialog();

             if (dr == DialogResult.OK)
             {
                 textBox1.Font = fontDialog1.Font;
                 textBox1.ForeColor = fontDialog1.Color;

             }
         }

字体样式  颜色

using System.IO;