C#利用FileSystemWatcher对文件进行监控

1、打开VS，选择Visual C#模板创建WPF应用程序。输入名称FileSystemWatcherTest，并指定其位置，点击确认按钮进入代码编写界面。

2、准备一个RichTextBox控件拖入到Form1界面中，点击右上角三角形，弹出RichTextBox任务，选择在父容器中停靠。该RichTextBox将用于监控外部记事本改变时显示改动后的内容。

3、添加一个名为MyWatcher的新类。可点击VS菜单项中的【项目】在其下拉菜单中找到【添加类】并点击，弹出添加新项窗口，在点击C#项中【类】，输入名称MyWatcher，点击【添加】按钮

4、在MyWatcher.cs页面中添加复制粘贴如下代码：

using System;

 

using System.Collections.Generic;

 

using System.IO;

 

using System.Linq;

 

using System.Text;

 

using System.Threading.Tasks;

namespace FileSystemWatcherTest

 

{

 

    class MyWatcher

 

    {

 

    

 

        public MyWatcher(dynamic FormTest,string path)

 

        {

 

            this.FormTest = FormTest;

 

            this.Path = path;

 

        }

 

        private  FileSystemWatcher watcher = null;

 

        private dynamic FormTest;

 

        internal  string Path

 

        {

 

            set

 

            {

 

                //watcher.Path = value;

 

                WatcherStrat(value);

 

            }

 

        }

 

        private  void WatcherStrat(string path)

 

        {

 

            if (watcher == null)

 

            {

 

                watcher = new FileSystemWatcher();

 

                System.IO.FileInfo f = new FileInfo(path);

 

                watcher.Path = f.DirectoryName ;

 

                watcher.Changed += new FileSystemEventHandler(OnChanged);

 

                watcher.EnableRaisingEvents = true;

 

                watcher.NotifyFilter = NotifyFilters.Attributes |

 

                                       NotifyFilters.CreationTime |

 

                                       NotifyFilters.DirectoryName |

 

                                       NotifyFilters.FileName |

 

                                       NotifyFilters.LastAccess |

 

                                       NotifyFilters.LastWrite |

 

                                       NotifyFilters.Security |

 

                                       NotifyFilters.Size;

 

                watcher.IncludeSubdirectories = true;

 

                watcher.Filter ="*"+ f.Extension;

 

            }

 

            else

 

            {

 

                System.IO.FileInfo f = new FileInfo(path);

 

                watcher.Path = f.FullName;

 

                watcher.Filter = "*" + f.Extension;

 

            }

 

        }

 

        private  void OnChanged(object source, FileSystemEventArgs e)

 

        {

 

            FormTest.TxtChanged(watcher.Path + "\\" + e.Name);

 

        }

 

    }

 

}

5、在Form1页面中添加复制粘贴如下代码：

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 FileSystemWatcherTest

 

{

 

    public partial class Form1 : Form

 

    {

 

        public Form1()

 

        {

 

            InitializeComponent();

 

            MyWatcher mwatcher = new MyWatcher(this, "1.txt");

 

        }

 

        public void TxtChanged(string path)

 

        {

 

            System.IO.StreamReader sr = new System.IO.StreamReader(path);

 

            string str = sr.ReadToEnd();

 

            sr.Close();

 

            RichTextBox1Text = str;

 

        }

        private delegate void RefleshUI(string s);

 

        private void Thread(string s)//UI线程要做的事情

 

        {

 

            this.richTextBox1.Text = s;

 

        }

 

        public string RichTextBox1Text

 

        {

 

            set

 

            {

 

                this.richTextBox1.Invoke(new RefleshUI(Thread), value);

 

            }

 

        }

 

    }

 

}

6、编译代码，生成解决方案。编译成功后，按F5执行。在生成目录下创建一个TXT文件，并修改其内容后保存，会发现richTextBox1中的内容发生了同样的变化。