C# 只得到 X 个文件

Question

我只想在无限循环以下一次处理 X 个文件。 下面的代码一次给我所有文件，如何只获取 X 个文件？

while (true)
{
    var files = new DirectoryInfo(@"path")
                .GetFiles()
                .OrderBy(p => p.LastWriteTimeUtc)
                .ToList();

    foreach (var f in files)
    {
        //do some processing
        Console.WriteLine(f.Name);

        f.Delete();
    }

    Thread.Sleep(5000);
}

Answer 1

您可以使用Skip() .Take(X)的组合，这将批量处理您的文件

Skip()：绕过序列中指定数量的元素，然后返回剩余的元素。

---

Take()：从序列的开头返回指定数量的连续元素。

批量处理文件，

var batchSize = 10;   //Decide batch size I considered 10 files in a batch
var skipBatch = 0     //Skip count
while (true)
{
    var files = new DirectoryInfo(@"path").GetFiles()
       .OrderBy(p => p.LastWriteTimeUtc).ToList(); //store all files

    var skipIntervals = skipBatch * batchSize;
    //Exit condition from infinity loop
    if(skipIntervals > files.Count)
        break;

    var filesInBatch = files.Skip(skipIntervals).Take(batchSize);
    foreach (var f in filesInBatch)
    {
        //do some processing
        Console.WriteLine(f.Name);
        f.Delete();
    }
    Thread.Sleep(5000);
    skipBatch++;  //Increment skipBatch count by 1 as this batch is processed
}

Answer 2

 while (true)
    {
        var files = new DirectoryInfo(@"path").GetFiles()
            .OrderBy(p => p.LastWriteTimeUtc).ToList();

        foreach (var f in files)
        {
           Thread.Sleep(5000);//should be up here
            //do some processing
            Console.WriteLine(f.Name);

            f.Delete();
        }

        
    }

thread.sleep 方法不在正确的位置

你总是可以使用 Await Task.Delay() 比 thread.sleep 好得多，因为它会使整个程序冻结，具体取决于你正在做什么

Answer 3

只保留一个柜台。 每次处理文件时，将其增加一个。 当它达到极限时，您就结束了该批次。

while (true)
{
    var counter = 0;
    var files = new DirectoryInfo(@"path").GetFiles()
        .OrderBy(p => p.LastWriteTimeUtc).ToList();
    foreach (var f in files)
    {
        //do some processing
        Console.WriteLine(f.Name);
        f.Delete();
        counter++;
        if (counter >= batchSize) 
        {
            Thread.Sleep(timeBetweenBatches);
            counter = 0;
        }
    }
    Thread.Sleep(5000);
}