Search and delete files async

Platform: Windows Programming Language: C# to be used as library in a console application Goal: Loop through directories async and delete files starting with any of the given strings in the fastest, most efficient way possible. Current Problem: Due to the massive amount of directories (> 400.000) and images (>50 per directory) walking one by one through all image files to see which ones must be deleted (>56.000 strings to search) takes days. The solution runs on a daily basis during the maintenance window which is 4 hours. Prefered Solution 1. Load dtHosts into List<string> 2. Enumerate directories async (eg using EnumerateDirectories) PS: note that there are > 400.000 directories and loading them at once with GetDirectories give OutOfMemoryExceptions 2.1. Start a new Thread for each directory (eg using [login to view URL]) 2.2. Enumarate files async (eg using EnumerateFiles) 2.2.1. Search if the imagefilename starts with any of the strings in dtHosts (eg [login to view URL] (e=>[login to view URL](e+"-"))). 2.2.1.1. If found 2.2.1.1.1. [login to view URL] imagefilename 2.2.1.1.2. delete the file. Function parameters String ImagePath: full path to the images, all directories under this must be checked. DataTable dtHosts: contains all HostIDs. These are the starting strings to be deleted. Example e.g. if a hostid exists of “-21234455” then all files beginning with “-21234455-“ must be deleted in all subdirectories. Attachments: • [login to view URL]: 2 directories from the 400.000 directories in total • [login to view URL]: current list of strings to search for.