递归函数内部的计数器 [英] Counter inside a recursive function

问题描述

我需要计算在此递归函数中删除的文件数。由于它是递归的，因此我不能使用 if 语句，并且C＃不支持全局变量。

I need to count the number of files deleted in this recursive function. Since it's recursive I cannot use if statements, and C# does not support global variables. Any alternatives?

static void DirSearch(string path)
{
    try
    {
        foreach (string dirPath in Directory.GetDirectories(path))
        {
            foreach (string filePath in Directory.GetFiles(dirPath))
            {
                string filename = Path.GetFileName(filePath);
                if (filename.Equals("desktop.txt"))
                {
                    File.Delete(filePath);
                    //count++
                }
                Console.WriteLine(filePath); // print files
            }
            Console.WriteLine(dirPath); // print directories
            DirSearch(dirPath);
        }
    }
    catch (System.Exception excpt)
    {
        Console.WriteLine(excpt.Message);
    }
}

推荐答案

一个方式是传递一些东西以供计数。我会使用 ref 来做到这一点，例如：

One way is to pass in something for it to count into. I'd do this using ref, for example:

static void DirSearch(string path, ref int count)
{
    try
    {
        foreach (string dirPath in Directory.GetDirectories(path))
        {
            foreach (string filePath in Directory.GetFiles(dirPath))
            {
                string filename = Path.GetFileName(filePath);
                if (filename.Equals("desktop.txt"))
                {
                    File.Delete(filePath);
                    count++
                }
                Console.WriteLine(filePath); // print files
            }
            Console.WriteLine(dirPath); // print directories
            DirSearch(dirPath,ref count);
        }
    }
    catch (System.Exception excpt)
    {
        Console.WriteLine(excpt.Message);
    }
}

然后称呼它：

int count = 0;

DirSearch(@"C:\SomePath",ref count);

然后，您可以像平常一样使用 count 您已在代码中注释掉了。

Then you can use count as normal as you had commented out in your code.

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