CODEWITHSUNDEEP
c#
Lakkes
Lakkes

Reputation: 25

File.Exist always return false

I know it's been asked a lot already, but I still can't get my code to work.

I built a little programm which lets you choose a product and asks for your information if you want to buy it. Every time the given information like name, address and so on... is saved in a single Excel file.

Now I want this file to be created if it doesn't already exists. It works to create one, and overwrite it. But if it exists, File.Exist will return a false anyway and overwrite the entire file with a new blank. It get's created to [user]\Documents folder.

My idea to check if the file already exists was this:

if (!File.Exists(@"C:\Bestellungen.xlsx"))
{
    CreateNewHistory(); // Method which creates the file in correct format
}
WriteData(); // Method to write given information to correct cells

The method for creating the file is simply:

private void CreateNewHistory()
{
    Excel excel = new Excel();

    excel.CreateNewFile();
    excel.SaveAs(@"Bestellungen.xlsx");
    ...
    // some cells get writte here, just for format
    ...
    excel.Close();
}

"Bestellungen" is German for "orders"... ;)

I suppose it has something to do with the way I pass the path into File.Exist but I am just clueless. I tried to copy the file into the bin\debug folder of my project. If it's there it works perfectly, but i really would like to know how i can find the file in the documents folder. I already tried put the absolute path, but it's always returning false.

If you need more information about the code let me know, I'm really new to c# or coding basically.

Upvotes: 1

Views: 880

Answers (3)

user9204685
user9204685

Reputation: 1

its throw a exception due to permission issue please change directory or give proper permission

Upvotes: -1

Panagiotis Kanavos
Panagiotis Kanavos

Reputation: 131189

You're saving the file using a relative path. The file will be saved in the program's working directory. Using C:\ will never work. In fact, you can't even write to the root folder without elevated privileges. Program Files is another folder you can't (and shouldn't even try) to save into, since 1995.

Older Windows versions would just throw an exception. Some developers would try to force permissions instead of fix their bugs, so newer versions redirect inappropriate writes to eg Documents or APPDATA. I suspect you run your program from Program Files and the OS redirected the file save operation to Documents.

You should use an absolute path to save files in the correct folder. User documents go to Documents, application files go to APPDATA etc. You can get the absolute path to each of those locations with Environment.GetFolderPath, and one of the SpecialFolder values like Desktop or MyDocuments eg :

var docFolder=Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
var filePath=Path.Combine(docFolder,"Bestellungen.xlsx");
excel.SaveAs(filePath);

And retrieve it the same way: 

var docFolder=Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
var filePath=Path.Combine(docFolder,"Bestellungen.xlsx");
if (!File.Exists(filePath))
...

The SpecialFolder enumeration explains the purpose of the various folders:

  • MyDocuments contains document files for the current user,
  • Desktop points to the current user's desktop
  • ApplicationData and LocalApplicatinoData contain application-specific files used by the current user, like logs and settings etc.
  • CommonDocuments, CommonDesktop, CommonApplicationDatacontain files used by all users on a computer

Upvotes: 4

shalitha senanayaka
shalitha senanayaka

Reputation: 2538

Use the Document folder to save your file.

  1. Get the User Document Folder 

    String path = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);

  2. Set the Filename

    string file="Bestellungen.xlsx";

  3. Finally, generate your actual path 

    String absolutePath  = System.IO.Path.Combine(path , file);

Upvotes: 0

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