Develop Reference

Windows Forms app on shared location, save file locally

My problem is that I have a windows forms application which is located on a shared location, which is doing some logic and at the end i need to export the data into an excel file.
But the excel file should be exported to the machine that the users is logged in, not on the shared server where the application is hosted ...
Any Ideas?
Example of the situation:
The location of the application is at 192.168.1.150\AppName\App.exe
I have access to this shared location and I'm starting the exe file from there.
I need the application to export an excel file to my computer on my desktop .... how?

If you think the folder "My Documents" is a good place to save the Excel file, then this code will help to get you the path:
var folderPath = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments)
or if you want to put the file on the Desktop:
var folderPath = Environment.GetFolderPath(Environment.SpecialFolder.DesktopDirectory)
The code works regardless of where the folder "My Documents" (or "Desktop") is located for the user (C:, D:, Network share, etc), or which language version his windows installation is using.
To combine with a time based file name:
var fileName = $"your_file_{DateTime.Now:yyMMddHHmmss}.xlsx";
var fullPath = Path.Combine(folderPath, fileName);
I often use time based file names to not overwrite if there is a previous file. (It would of course overwrite if created the same second)
If you want a file name that is guaranteed to be unique you can use a Guid instead of DateTime:
var fileName = $"your_file_{Guid.NewGuid():N}.xlsx";
If the file is just used "within the program" you can also store it in the temporary files folder. To get the path to the temporary files folder you write var folderPath = Path.GetTempPath()
Hope this helps!

Why don't you just use Save File Dialog and save the excel file where you want? Something like this:
private void SaveFile_FileOk(object sender, CancelEventArgs e)
{
string name = SaveFile.FileName;
string[] savearray = new string[] { "some test:" }
File.WriteAllLines(name, savearray);
//this is just an example, your excel file goes here.
}
And on your button to save:
SaveFile.ShowDialog();
You can choose the path for where you want to save...

Storing MSSQL LocalDB for Application

I have been using a LocalDB.mdf file to build my application, but now need to use it in production and create an installable application.
After research, it seems the best place to store such a file is in the /Appdata/Local/ folder.
I intend to create a new LocalDB.mdf file in there if it doesnt already exist, or has been deleted.
I have a pre-made LocalDB.mdf file in my App Resources, which I wanted to copy into this /Appdata/Local/ folder on first run, but I am seeing an Access is denied error.
I can create a blank file ok to that folder.
Here is the code:
string appDataFolder = Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
string dvAppDataFolder = appDataFolder + #"\MyApp";
AppDomain.CurrentDomain.SetData("DataDirectory", dvAppDataFolder);
if (!Directory.Exists(dvAppDataFolder))
Directory.CreateDirectory(dvAppDataFolder);
if (!File.Exists(dvAppDataFolder + "LocalDB.mdf"))
{
File.WriteAllBytes(dvAppDataFolder, LokiServer.Properties.Resources.newDB);
}
In addition, Am I going about this the right way?

This line
if (!File.Exists(dvAppDataFolder + "LocalDB.mdf"))
is probably wrong. Missing the backslash, better to use Path.Combine instead of a string concatenation.
Finally, you want to write to a file not to a folder
string fileName = Path.Combine(dvAppDataFolder,"LocalDB.mdf");
if (!File.Exists(fileName))
{
File.WriteAllBytes(fileName, LokiServer.Properties.Resources.newDB);
}
Are you doing it right? It depends. If your app data should be kept separated for each user of your target machine then you are right, but if you want your database to be available to all users of that machine then use
string appDataFolder = Environment.GetFolderPath
(Environment.SpecialFolder.CommonApplicationData);

C# Saving files on different PC's

The program I am writing is a stock inventory system.
So the PC I wrote the program on can locate the files and folders to update on the PC as necessary as the path is valid.
string path = "C:\\Users\\ThisPC\\Documents\\Stock Documents\\Reciepts";
if (!Directory.Exists("C:\\Users\\ThisPC\\Documents\\Stock Documents\\Reciepts"))
{
Directory.CreateDirectory(path);
}
var fileName = #"c:\Users\ThisPC\Documents\Stock Documents\Tyre_File.xml";
This line is also used when I am updating quantities when an order is taken.
So obviously when I run this program in visual studio on another PC this path isn't recognized.
Is there a way that I can add a pointer to create and store my folder and documents in the My Documents on any pc the program loads in?
UPDATE-------------------------------------------------------
string path = "C:\\Users\\ThisPC\\Documents\\Stock Documents\\Customer Reciepts";
if (!Directory.Exists("C:\\Users\\ThisPC\\Documents\\Stock Documents\\Customer Reciepts"))
{
Directory.CreateDirectory(path);
}
This is the only one it wont work for, it creates a folder within a folder when the form is loaded, but your method doesnt work for that?

I believe that
Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
is what you are looking for

You want the environment variable for MyDocuments, which will be unique for each user/computer.
String path = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);

c# using filename to match database value with existing file in directory

i am writing a console app in c# to check if file 'id' in sql server table matches filename of file on local directory...i know how to use filename to check a location(all this does is check file exists in local directory)...
for example if there was an entry in a sql table of value '925677bb-cabb-4ff1-8c90-3e130a77b366'...i would want to perform check on location (c:\...) where any files with that filename would exist, ie '925677bb-cabb-4ff1-8c90-3e130a77b366.jpg'
what would be the best way to do this?

You could use the File.Exists function:
string id = ... go and fetch from your db
string filename = Path.ChangeExtension(Path.Combine(#"c:\somefolder", id), ".jpg");
if (File.Exists(filename))
{
// the file c:\somefolder\925677bb-cabb-4ff1-8c90-3e130a77b366.jpg exists
}

Make use of Directory.GetFiles(), like this
string []files = Directory.GetFiles(#"C:\", "925677bb-cabb-4ff1-8c90-3e130a77b366*.jpg")
in this way you will get all files that starts with specified string in C:\ directory
So if the array files is empty, there is no any file like that, otherwise, there is at least one.

Read a file from an unknown location?

I have got this read file code from microsoft
#"C:\Users\computing\Documents\mikec\assignment2\task_2.txt"
That works fine when im working on it, but when i am to hand in this assignment my lecturer isn't going to have the same directory as me.
So i was wondering if there is a way to read it from just the file the program is held in?.
I was thinking i could add it as a resource but im not sure if that is the correct way for the assignment it is meant to allow in any file.
Thanks

You can skip the path - this will read file from the working directory of the program.
Just #"task_2.txt" will do.
UPDATE: Please note that method won't work in some circumstances. If your lecturer uses some automated runner (script, application whatsoever) to verify your app then #ken2k's solution will be much more robust.

If you want to read a file from the directory the program is in, then use
using System.IO;
...
string myFileName = "file.txt";
string myFilePath = Path.Combine(Application.StartupPath, myFileName);
EDIT:
More generic solution for non-winforms applications:
string myFilePath = Path.Combine(Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location), myFileName);

If it is a command line application, you should take the file name as a command line argument instead of using a fixed path. Something along the lines of;
public static void Main(string[] args)
{
if (args == null || args.Length != 1)
{
Console.WriteLine("Parameters are not ok, usage: ...");
return;
}
string filename = args[0];
...
...should let you get the filename from the command.

You could use the GetFolderPath method to get the documents folder of the current user:
Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments)
and to exemplify:
string myDocuments = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
string file = Path.Combine(myDocuments, #"mikec\assignment2\task_2.txt");
// TODO: do something with the file like reading it for example
string contents = File.ReadAllText(file);

Use the relative path.
you can put your file inside the folder where your application resides.
you can use Directory.GetCurrentDirectory().ToString() method to get the current folder of the application in. if you put your files inside a sub folder you can use
Directory.GetCurrentDirectory().ToString() + "\subfolderName\"
File.OpenRead(Directory.GetCurrentDirectory().ToString() + "\fileName.extension")
StreamReader file = new StreamReader(File.OpenRead(Directory.GetCurrentDirectory().ToString() + ""));
string fileTexts = file.ReadToEnd();