C#文件创建和读取&OpenFIleDialog&SaveFileDialog用法

在做winform简易文件处理器时需要从系统资源中读取和创建txt文件，不多说，具体方法如下，注意完整的文件路径，比如：C:Users86159Documents记事本txt文件聪敏人傻子和奴才-鲁迅.txt

private void createFile(string fullPath, string content)   //参数：文件路径，文本内容
        {
            FileStream file = File.OpenWrite(fullPath);    //打开一个现有文件或创建一个文件来写入 
            StreamWriter writer = new StreamWriter(file);   //创建写入流

            writer.WriteLine(content);   //写入数据
            writer.Flush();      //清理写入器的缓冲区
            writer.Close();       //关闭写入器
            Console.WriteLine("文件保存成功！");
        }
        
        //文件读取方法
        private string readFile(string fullPath)   //传入参数：文件路径
        {
            FileStream file = File.OpenRead(fullPath);   //打开现有问价进行读操作
            StreamReader reader = new StreamReader(file);    //创建读取流

            string content = "";
            content = reader.ReadToEnd();   //从file中读数据
            reader.Dispose();     //释放reader占用的file资源  
            reader.Close();       //关闭文件读取器
            Console.WriteLine("文件读取成功！");
            return content;      //返回文本内容
        }
    }
}

顺带将OpenFIleDialog&SaveFileDialog用法记录一下：

 //打开 
        private void 打开ToolStripMenuItem_Click(object sender, EventArgs e)
        {
            OpenFileDialog openFileDialog = new OpenFileDialog();
            openFileDialog.Title = "请选择文件（.txt）：";    //设置对话框标题
            openFileDialog.Filter = "(*.txt)|*.txt";      //设置文件类型。不设置默认打开上次路径
            openFileDialog.InitialDirectory = startPath;   //设置打开初始目录

            if(openFileDialog.ShowDialog() == DialogResult.OK)
            {
                fullPath = openFileDialog.FileName;      //文件全路径
                fileName = fullPath.Substring(fullPath.LastIndexOf("\") + 1);   //文件名和后缀
                startPath = fullPath.Substring(0,fullPath.LastIndexOf("\"));  //获取文件路径

                Console.WriteLine("fullPath = " + fullPath);
                Console.WriteLine("fileName = " + fileName);
                Console.WriteLine("startPath = " + startPath);

                text = readFile(fullPath);    //调用readFile方法
                Console.WriteLine(fileName+"的内容：n"+text);
                richTextBox1.Text = text;    //更新富文本框内容

            }
        }

        //保存
        private void 保存ToolStripMenuItem_Click(object sender, EventArgs e)
        {
                SaveFileDialog save = new SaveFileDialog();
                save.Filter = "(*.txt)|*.txt";     //设置保存类型
                save.Title = "请选择保存位置和文件名";   //对话框标题
                save.InitialDirectory = startPath;   //设置初始打开目录

                if (save.ShowDialog() == DialogResult.OK)
                {

                    fullPath = save.FileName;
                    fileName = fullPath.Substring(fullPath.LastIndexOf("\") + 1);   //文件名
                    startPath = fullPath.Substring(0, fullPath.LastIndexOf("\"));   //改写初始文件路径

                    Console.WriteLine("fileName = "+fileName);
                    Console.WriteLine("startPath = " + startPath);

                    createFile(fullPath, text);   //调用createFile方法创建txt文件
                }
        }

StreamWriter 类的方法：

StreamReader 类的方法：