c#使用filesystemwatcher监视文件系统的变化

#region 监视文件夹的变化
            filesystemwatcher watcher = new filesystemwatcher();
            watcher.path = "f:\\";
            watcher.notifyfilter =//被监控的方面
               notifyfilters.lastwrite |
               notifyfilters.filename |
               notifyfilters.directoryname;

            // 订阅一些事件，当它被触发时（.net(windows)底层触发它，我们不用管），执行我们的方法
            watcher.changed += (object source, filesystemeventargs e) =>
            {
                console.writeline("文件{0}已经被修改,修改类型{1}", e.fullpath, e.changetype.tostring());
            };
            watcher.created += (object source, filesystemeventargs e) =>
            {
                console.writeline("文件{0}被建立", e.fullpath);
            };
            watcher.deleted += (object source, filesystemeventargs e) =>
            {
                console.writeline("文件{0}已经被删除", e.fullpath);
            };
            watcher.renamed += (object source, renamedeventargs e) =>
            {
                console.writeline("文件{0}的名称已经从{1}变成了{2}", e.oldfullpath, e.oldname, e.name);
            };

            // 为true表示开启filesystemwatcher组件，反之我们的监控将不启作用
            watcher.enableraisingevents = true;
            #endregion

另外，告诉大家一个 xor异或运算的使用技巧，就是它可以在不引入第三个变量的情况下，交替两个变量的值，你的变量可以是数值，也可以是字符，如果是字符，我们需要使用它的hashcode值进行xor运算。

#region xor两个变量交换
            int a = 2;
            int b = 3;
            console.writeline("a={0}", a);
            console.writeline("b={0}", b);
            a = a ^ b ^ (b = a);
            console.writeline("a={0}", a);
            console.writeline("b={0}", b);
            #endregion