C#实时监控文件系统变化的实战指南

// 创建监听器
FileSystemWatcher watcher = new FileSystemWatcher();
watcher.Path = @"C:\Your\Target\Directory"; // 监听目录
watcher.Filter = "*.log"; // 仅监控 .log 文件
watcher.IncludeSubdirectories = true; // 是否包含子目录

// 注册事件处理
watcher.Created += OnChanged;
watcher.Changed += OnChanged;
watcher.Deleted += OnChanged;
watcher.Renamed += OnRenamed;

// 启动监听
watcher.EnableRaisingEvents = true;

private static void OnChanged(object source, FileSystemEventArgs e) {
    // 延迟处理（避免“假事件”）
    if (e.ChangeType == WatcherChangeTypes.Changed) {
        Thread.Sleep(500); // 等待文件完全写入
        ProcessFile(e.FullPath);
    }
}

try {
    watcher.EnableRaisingEvents = true;
} catch (Exception ex) {
    Console.WriteLine($"监听启动失败: {ex.Message}");
}

// 释放资源
watcher.Dispose();

class Program {
    static void Main(string[] args) {
        FileSystemWatcher watcher = new FileSystemWatcher();
        watcher.Path = @"C:\Logs";
        watcher.Filter = "*.log";
        watcher.IncludeSubdirectories = true;

        watcher.Created += OnLogChanged;
        watcher.Changed += OnLogChanged;

        watcher.EnableRaisingEvents = true;

        Console.WriteLine("日志监控已启动，按任意键退出...");
        Console.ReadKey();
    }

    private static void OnLogChanged(object sender, FileSystemEventArgs e) {
        Thread.Sleep(500); // 等待文件写入完成
        try {
            var lines = File.ReadAllLines(e.FullPath);
            foreach (var line in lines) {
                if (line.Contains("ERROR")) {
                    Console.WriteLine($"[ERROR] {line}");
                }
            }
        } catch (Exception ex) {
            Console.WriteLine($"处理日志失败: {ex.Message}");
        }
    }
}

watcher.InternalBufferSize = 64 * 1024; // 默认 8KB