System.IO.Directory.Delete(installPath, true);
System.IO.Directory.CreateDirectory(installPath);

下面的示例显示了如何做到这一点。它首先创建一些目录和文件，然后通过Directory.Delete（topPath，true）；：

    static void Main(string[] args)
    {
        string topPath = @"C:\NewDirectory";
        string subPath = @"C:\NewDirectory\NewSubDirectory";

        try
        {
            Directory.CreateDirectory(subPath);

            using (StreamWriter writer = File.CreateText(subPath + @"\example.txt"))
            {
                writer.WriteLine("content added");
            }

            Directory.Delete(topPath, true);

            bool directoryExists = Directory.Exists(topPath);

            Console.WriteLine("top-level directory exists: " + directoryExists);
        }
        catch (Exception e)
        {
            Console.WriteLine("The process failed: {0}", e.Message);
        }
    }

它取自https://msdn.microsoft.com/en-us/library/fxeahc5f（v=vs.110）.aspx。

要删除文件夹，这是使用文本框的代码和使用System.IO；的按钮：

private void Deletebt_Click(object sender, EventArgs e)
{
    System.IO.DirectoryInfo myDirInfo = new DirectoryInfo(@"" + delete.Text);

    foreach (FileInfo file in myDirInfo.GetFiles())
    {
       file.Delete();
    }
    foreach (DirectoryInfo dir in myDirInfo.GetDirectories())
    {
       dir.Delete(true);
    }
}

DirectoryInfo.GetFileSystemInfos同时返回文件和目录：-

new DirectoryInfo(targetDir).GetFileSystemInfos().ToList().ForEach(x => x.Delete());

或者如果要递归删除：-

        new DirectoryInfo(targetDir).GetFileSystemInfos().ToList().ForEach(x =>
        {
            if (x is DirectoryInfo di)
                di.Delete(true);
            else
                x.Delete();
        });

 foreach (string file in System.IO.Directory.GetFiles(path))
 {
    System.IO.File.Delete(file);
 }

 foreach (string subDirectory in System.IO.Directory.GetDirectories(path))
 {
     System.IO.Directory.Delete(subDirectory,true); 
 } 

这将显示我们如何删除文件夹并使用文本框进行检查

using System.IO;
namespace delete_the_folder
{
public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    private void Deletebt_Click(object sender, EventArgs e)
    {
        //the  first you should write the folder place
        if (Pathfolder.Text=="")
        {
            MessageBox.Show("ples write the path of the folder");
            Pathfolder.Select();
            //return;
        }

        FileAttributes attr = File.GetAttributes(@Pathfolder.Text);

        if (attr.HasFlag(FileAttributes.Directory))
            MessageBox.Show("Its a directory");
        else
            MessageBox.Show("Its a file");

        string path = Pathfolder.Text;
        FileInfo myfileinf = new FileInfo(path);
        myfileinf.Delete();

    }


}

}