小编Der*_*rek的帖子

我在编程语言中搜索了API的定义,但我仍然觉得很难理解.

任何人都可以用简单的外行人的话来建议我:

1. 什么是API？
2. 怎么用？
3. 何时何地使用？

chrome.tabs.onUpdated.addListener(checkForValidUrl);
function checkForValidUrl(tabId, changeInfo, tab) {
    if (tab.url.indexOf('https') > -1) {
        var tabURL = tab.url;
        console.log("\n<TimeStamp>" + getTimestamp() + "</TimeStamp><Browser>Chrome</Browser><URL>" + tabURL + "</URL>\n");
        window.requestFileSystem(window.PERSISTENT, 5 * 1024 * 1024, initFs);

        function initFs(fs) {
            fs.root.getFile
            ('log.txt', { create: true, exclusive: true }, function (fileEntry) {
                fileEntry.isFile = true;
                fileEntry.name = 'log.txt';
                fileEntry.fullPath = '/log.txt';
                fileEntry.createWriter(function (fileWriter) {
                    fileWriter.seek(fileWriter.length);
                    var bb = new BlobBuilder();
                    bb.append("\n<TimeStamp>" + getTimestamp() + "</TimeStamp><Browser>Chrome</Browser><URL>" + tabURL + "</URL>\n");
                    fileWriter.write(bb.getBlob('text/plain'));
                });
            });
        }
    }
}

背景信息:我正在使用服务中实现的FileSystemWatcher类来监视文件中的更改.下面是触发onCreate事件时抛出Argument Exception(Path不是合法形式)的编码部分.

FileMonitor.CS

public partial class FileMonitor:ServiceBase
{
 public FileSystemWatcher Watcher = new FileSystemWatcher();

    Private void FileWatcher()
    {
    FileActionHandler ActionHandler = new FileActionHandler();
    Watcher.Created += new FileSystemEventHandler(ActionHandler.onCreate);
    Watcher.Deleted += new FileSystemEventHandler(ActionHandler.onDelete);
    Watcher.Renamed += new RenamedEventHandler(ActionHandler.onRenamed);
    Watcher.EnableRaisingEvents = true;
    }
}

FileActionHandler.CS

 class FileActionHandler
 {
  FileMonitor FileMon = new FileMonitor();
  public void onCreate/onRename/onDelete(object source, FileSystemEventArgs e)
    {
      try
      {
       FileMon.Watcher.EnableRaisingEvents = false;
      }
      catch
      {
       /* Exception Code */
      }
      finally
      {
       FileMon.Watcher.EnableRaisingEvents = true;
      }
    }
  }

问题:任何人都可以告诉我为什么抛出异常以及如何解决它？

我有这个字符串

     AnyText: "jonathon" <usernameredacted@example.com>

使用正则表达式所需的输出

     AnyText: <usernameredacted@example.com>

省略之间的任何事情!

我仍然是正则表达的新秀.那里的任何人都能帮我解决上述场景的匹配和替换表达吗？

这是我的单线程代码:

OnStart 
{
 FileSystemWatcher Watcher = new FileSystemWatcher();
 Watcher.NotifyFilter = NotifyFilters.FileName | NotifyFilters.LastWrite |NotifyFilters.CreationTime | NotifyFilters.DirectoryName;
 FileActionHandler ActionHandler = new FileActionHandler();
 Watcher.Created += new FileSystemEventHandler(ActionHandler.onCreate);
}

onCreate(object source,FileSystemEventArgs e)
{
 try
 {
 FileInfo file = new FileInfo (e.FullPath);
 String output = <FileName>File.Name + <FullPath>File.FullName + <FileSize>File.Length +  <CreationTime>File.CreationTime + <LastAccess>File.LastAccess + <LastWriteTime>File.LastWriteTime;
 LogToTextFile(output);
 }
 catch
 {
 LogToTextFile(ex.GetBaseException().Message);
 }
}

private void LogToTextFile(String s)
{
FileStream fileStream = new FileStream(@"c:\Log.txt", FileMode.Append, FileAccess.Write);
StreamWriter sw = new StreamWriter(fileStream);
sw.WriteLine(s);
sw.Flush();
sw.Close();
fileStream.Close(); …

避免像

(1)进程无法访问该文件,因为它被另一个进程使用

在进行任何进一步处理之前,我使用以下方法测试文件的可访问性.

private bool CheckIfFileBeingUsed(string FilePath)
    {
        FileStream Fs = null;
        try
        {
            Fs = File.Open(FilePath, FileMode.Open, FileAccess.Read, FileShare.None);
            Fs.Close();
        }
        catch (Exception)
        {
            return true; //Error File is being used
        }
        return false; //File is not being used.
    }

任何人都可以告诉我有任何Windows API或其他解决方案来测试文件可访问性而不是上面的File.Open方法吗？