您可以使用 SaveFileDialog 类。示例：

var dialog = new SaveFileDialog();
dialog.Filter = "Archive (*.rar)|*.rar";

var result = dialog.ShowDialog(); //shows save file dialog
if(result == DialogResult.OK)
{
    Console.WriteLine ("writing to: " + dialog.FileName); //prints the file to save

    var wClient = new WebClient();
    wClient.DownloadFile("WebLinkHere", dialog.FileName);
}

将显示下一个对话框，如果您搜索下一个文件夹

will show next dialog and if you search for next folder

应用程序将打印：

writing to: C:\Temp\archiveName.rar