🦉 🔖 [CheatSheet] - Filesystem APIs

[ppr (Peter Preuss)]

This CheatSheet introduces the basic use of available functionalities provided by the .Net API in order to deal with the filesystem. With further examples also special cases are presented.

Basic Usage

System.IO.Directory

Directory offers some static methods for basic operations on folder and subfolders

arrFullFilePaths | String() = Directory.GetFiles("C:\_demo\FileSystem\SubfolderA")

Visuals

System.IO.DirectoryInfo

The DirectoryInfo class offers instance methods for basic operations on folder and subfolders

arrFilesFI = new DirectoryInfo("C:\_demo\FileSystem\SubfolderA").GetFiles

Visuals

System.IO File / FileInfo

Similar to above we do have the same for files

File.GetCreationTime("C:\_demo\FileSystem\SubfolderA\Inventory_2020.xlsx")
new FileInfo("C:\_demo\FileSystem\SubfolderA\Inventory_2020.xlsx").CreationTime

Visuals

File Retrieval

MyDirPathVar = "C:\_demo\FileSystem\SubfolderA"

arrFullFilePaths | datatype: String() =

Directory.GetFiles(MyDirPathVar)
Directory.GetFiles(MyDirPathVar,"*.txt")
Directory.GetFiles(MyDirPathVar,"Report*.xlsx")
Directory.GetFiles(MyDirPathVar,"*.*",SearchOption.AllDirectories)

arrFilesFI | datatype: FileInfo() =

New DirectoryInfo(MyDirPathVar).GetFiles()
New DirectoryInfo(MyDirPathVar).GetFiles("Report*.xlsx")
New DirectoryInfo(MyDirPathVar).GetFiles("*.*",SearchOption.AllDirectories)

Folder Retrieval

Directory.GetDirectories("C:\_demo\FileSystem\")
Directory.GetDirectories("C:\_demo\FileSystem","*",SearchOption.AllDirectories)
new DirectoryInfo("C:\_demo\FileSystem").GetDirectories()
new DirectoryInfo("C:\_demo\FileSystem").GetDirectories("*", SearchOption.AllDirectories)

FileSystem Entries Retrieval

Directory.GetFileSystemEntries("C:\_demo\FileSystem")
Directory.GetFileSystemEntries("C:\_demo\FileSystem","*", SearchOption.AllDirectories)
new DirectoryInfo("C:\_demo\FileSystem").GetFileSystemInfos()
new DirectoryInfo("C:\_demo\FileSystem").GetFileSystemInfos("*", SearchOption.AllDirectories)
new DirectoryInfo("C:\_demo\FileSystem").EnumerateFiles("*",SearchOption.AllDirectories)

File Property Retrieval

Path.GetFileNameWithoutExtension("C:\Temp\abc.txt")
New FileInfo("C:\Temp\abc.txt").Extension
File.GetCreationTime("C:\Temp\abc.txt")
New FileInfo("C:\Temp\abc.txt").CreationTime

File Paths

Path.Combine("C:\","Temp","abc.txt")
Path.GetDirectoryName("C:\Temp\abc.txt")
new FileInfo("C:\Temp\abc.txt").DirectoryName
New FileInfo("C:\Temp\SubfolderA\abc.txt").Directory.Parent
New FileInfo("C:\Temp\SubfolderA\abc.txt").Folder
New FileInfo("C:\Temp\SubfolderA\abc.txt").Folder.Split({"\"}, StringSplitOptions.RemoveEmptyEntries)
("C:\Temp\SubfolderA\abc.txt").Folder.Split({"\"}, StringSplitOptions.RemoveEmptyEntries)

File Retrieval - Advanced Filtering

Filter - Creation Time

arrFilesFI  = new DirectoryInfo("C:\").GetFiles().Where(Function (x) x.CreationTime.Date < Now.Date).toArray
myFileInfo = new DirectoryInfo("C:\").GetFiles().OrderBy(Function (x) x.CreationTime).Last()
myFileInfo = new DirectoryInfo("C:\").GetFiles().OrderBy(Function (x) x.CreationTime).First()

Filter on: x.CreationTime.Date < Now.Date - get all files created before today
Retrieve: x.CreationTime).Last() - newest created file FileInfo
Retrieve: x.CreationTime).First() - oldest created file FileInfo

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Filter - Regex Pattern

Filter all file names matching a regex pattern:

(From fi In New DirectoryInfo("C:\_RPA\_Demo").GetFiles()
Where Regex.IsMAtch(fi.Name,"\(\d+\)\.docx$", RegexOptions.IgnoreCase)
Select fi.FullName).toArray

Filter - Filetype Extension

Filter on multiple file extensions:

DirectoryInfo based

new DirectoryInfo("C:\").GetFiles().Where(Function (x) {".pdf",".txt"}.Contains(x.Extension)).toArray

Directory.GetFiles based

arrFullFilePaths | String() - String Array =

(From f in Directory.GetFiles(MyDirPathVar)
Let xt = Path.GetExtension(f).toUpper.Replace(".","")
Where {"PDF","TXT","XML"}.Contains(xt)
Select fp = f).toArray

References

[CheatSheet] VB.Net CheatSheet Catalogue

This topic references the different CheatSheets related to VB.Net It will be updated on new published CheatSheets as well. Regular Expressions - RegEx File System API About the CheatSheet Series The CheatSheet series covers various programming topics and lists selected API statements. In addition to the help given, the CheatSheets can also be used to check one’s own knowledge and to explore further development approaches. Recommendations Training courses from Academy Debugging course f…

Questions

For questions on your file system API case open a new topic and get individual support