Reading Excel in C# - c#

I have code in C# like this.
xlWorkBook = xlApp.Workbooks.Open("data.xls", 0, true, 5, "", "", true, Microsoft.Office.Interop.Excel.XlPlatform.xlWindows, "\t", false, false, 0, true, 1, 0);
I have data.xls file where .exe are located.
When I compile and then run .exe, I'm receiving error that data.xls could not be found.
What I do wrong?

If your xls will always be in the same location as your .exe, you can use this to get a path that won't be hardcoded to the build directory:
string directory = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
string path = Path.Combine(directory, "data.xls");

By default, Excel assumes that the folder of the file specified is user's "My Documents" directory. If the file is not there, any attempt to open it will fail.
By specifying an absolute path to the file, you can ensure that correct file is being picked up. Make sure the file exists.
Eg-
//file is in D:\TestFolder, and its called abc.xlsx
xlApp.Workbooks.Open( #"D:\TestFolder\abc.xlsx", ....
Hope it helps.
Other answers show you how to use the absolute path to the file which is kept at certain location.

Unless you've changed your project settings, when your C# app gets built, it is being built in a bin/debug (or bin/release) folder under your project. When you run from the IDE, that's the current working directory for your app.
Try using an absolute path, or moving the data.xls file into your application's bin/debug folder.
When you specify the absolute path, make sure to prefix the string with an # sign to escape out the slashes. string path = #"c:\data\excel\data.xls";
UPDATE:
If you need to use a relative path, I would get the absolute path based on the relative patht this way:
FileInfo fileInfo = new FileInfo("data.xls");
String path = fileInfo.FullName;
This might be preferable to getting the full path based on the .exe location, because it will work even if the CWD is not the same as the .exe location.

It depends on how exactly you run your application. What makes you think that application is being ran in the same directory where executable file is located? Most probably you just forgot to set the working directory right. How to do it? See this Q&A.

i think this is a problem with the location of the Excel file. the application's working directory is not where the .exe file is located, but probably in the bin/debug folder.

Related

ReadAllLines() local directory not working

For some reason the ReadAllLines() looks in the wrong folder.
string[] LoadLines = File.ReadAllLines(#"Assets\\UserFile.txt");
The "Assets\UserFile.txt" is located where the exe file is.
The Debugger throws a System.IO.DirectoryNotFoundException with a comment:
"Could not find a part of the path C:\WINDOWS\SysWOW64\Assets\UserFile.txt"
Why is it checking in the wrong folder?
Try this...
string path = Path.Combine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), #"Assets\UserFile.txt");
string[] lines= File.ReadAllLines(path);
Note: This will look in the folder you are executing from so make sure the folder/file exists in there.
If the executing folder is your bin folder, ensure that the file property is set to "Content" and "Always copy" or "Copy when newer" within Visual Studio.
Relative path names are resolved relative to the working directory of the process, not relative to the executable. So presumably your process has a working directory of c:\Windows\SysWOW64.
If your code needs to load assets that are effectively bundled with the application, I'd use embedded resources as a way of not having to worry about physical file paths.

Folder in windows form c#

This is my first windows form application.
I need to work with folders that I have created in my project and I need to access the Data folder where I put .txt files.
I try :
string fileName = #"Data\TextFile1.txt";
string path = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, fileName);
but i keep receiving this error :
impossible find part of path.
How can I combine the folder's path with file's name so when I release the project all works well?
This is what I do in an asp.net application:
Path.Combine(HttpRuntime.AppDomainAppPath, "Folder/FileName.txt");
Your data files need to be available in output folder along with you application .exe file. to do that:
Open properties of each file in Data folder.
Select Copy Always against Copy to output directory
Then build application
This will copy Data folder along with all files in Bin\Debug folder and will work with your existing code.
If I understand correctly, you are trying to read some file you have added to your solution in Visual Studio.
First, to have those files "deployed", click on them in the Solution Explorer, go to the Properties tool and have a look at the "Copy to Output Directory". Default is "Do not copy". Change that setting to "Copy always" or "Copy if newer". Now your files will be copied to the output directory when you build the solution.
Then, to get the current assembly path at runtime, have a look at:
Getting the path of the current assembly
string path = (new System.Uri(Assembly.GetExecutingAssembly().CodeBase)).AbsolutePath;
from the assembly path, you can get the containing folder's path, then you can use Path.Combine() to get your desired file path.
in C# .NET you can easy use the Environment Properties when working with Forms.
If you want e.g. the Appdata Path do this:
string MyPath = Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData) + #"\" + MyFileName;
But please get sure that the File/Path Exists!
For this you can use File.Exists -Function:
if(File.Exists(MyPath))
{
//Do Something
}
(For File-Class you need the System.IO namespace!)
EDIT:
Example:
string MyPath = Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData) + #"\MyConfig.txt";
if(File.Exists(MyPath))
{
MessageBox.Show($"{MyPath} exists!");
}
Hope that helped ;)
I would not create any path inside the application if possible. The NET framework provides the application configuration file for this kind of problems. You should simply add this section to your configuration file (app.config when developing, then application.exe.config after compilation)
<configuration>
<appSettings>
<add key="mydatafolder" value="e:\whateverpathyoulike"></add>
</appSettings>
</configuration>
Then at runtime read that value from your code
string path = ConfigurationManager.AppSettings["mydatafolder"];
path = Path.Combine(path, fileName);
This is easily modifiable both automatically or manually to adapt to any environment you find on the destination computers

C#.NET - Error Logging and Relative File Paths

I have a class in C# that saves an error message in a log file in case of an exception. Now I want to save the log file in the same folder containing the application's (in my case, a website) files. I tried using Environment.CurrentDirectory however it is not retrieving the path to my website. What can I do please to make use of a relative file path which points inside the website's directory?
Here is the class' code. As you can see, the path is absolute. I want to change it to a relative file path pointing to a folder in my website's directory.
Usually Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location) returns the path where the current assembly resides. You could use
string logName = Path.Combine(Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location), "MyLogFile.log");
to create the log file name.
Question is really whether logging to the application's folder is permitted by the OS. Also, for Web-applications, the log file would be publically visible and accessible through the web browser.
For a website use:
HttpContext.Current.Server.MapPath("~/");
You might also could try this solution:
string path = AppDomain.CurrentDomain.BaseDirectory + "anotherFolder";
This would put the base dir of the app and a folder inside of the project!

Reading Excel File in C# using MS Visual Studio 2010: How to give Relative Path?

I am reading an Excel file in the following way:
string path = #"C:\Users\myUserName\inputfile.xlsx";
Excel.Application app = new Application();
Excel.Workbook workbook = app.Workbooks.Open(path, 0, true, 5, "", "", true, Excel.XlPlatform.xlWindows, "\t", false, false, 0, true, 1, 0);
I was wondering if there is any way I can give relative path instead of hard-coded absolute path. What I have in mind is to put the inputfile.xlsx in the same directory and do something like...
string path = #"inputfile.xlsx";
But, it gives "COMException unhandled..", "inputfile.xlsx not found"
use the following code to get the .exe location:
‫‪
string localPath = System.IO.Path.GetDirectoryName
‫‪(System.Reflection.Assembly.GetExecutingAssembly().Location‬‬)
You can use Directory.GetCurrentDirectory() to understand what your current directory is, if there is any doubt.
If Excel is not finding the file, chances are very good that you misunderstand what the current directory is. Construct the path relative to the directory returned by GetCurrentDirectory().
FYI, running the app stand-alone, in a debugger, and in a MS Test unit test will all set different current directories. The reason is that the executable is started from a different directory in each case.
Make sure the excel file is in the same folder as the executable, or alternatively make sure that the relative path is correct, relative to the directory containing the executable.
If the excel file is included in your project, you could also right click on it in the solution explorer, click on properties, and set the "Copy to Output Directory" to something like "Copy always". This will cause the file to be placed in the projects output directory. A relative path would then only include the name of the file.

Environment PATH variable affecting Relative File Path(s)

I had this console application. Now i have added Environment variable PATH to its setup so that it can be executed from any location through Console. Strangely, the same application is breaking after this change.
Installation directory contains, BIN and CONFIG folder. Exe is placed inside BIN folder.
I have this line of code,
WriteToFile(#"..\Config\Settings.xml")
The path used to write to a file Settings.xml inside Config folder inside the INSTALLATION DIRECTORY. However, now it tries to write to settings.xml inside Config folder at EXECUTION PATH.
So, if i execute my app from console as c:/users/guest/app.exe, it would try to interpret path relative to this location AND NOT relative to installation directory for the application.
Any help, suggestions?
Get the path of the executing assembly then add to it the folder and file name:
string pathOfExecutingAssembly = System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location);
string settingsPath = pathOfExecutingAssembly + "\\..\\Config\\Settings.xml"
Why don't you try getting the Executing Application's Path and append it before the path where you want to save
Path starting from \ means: start from the root directory on the current drive. \Config\Settings.xml executed from any C subdirectory gives: C:\Config\Settings.xml.
BTW, do you post exact code? It should be WriteToFile(#"\Config\Settings.xml") or WriteToFile("\Config\Settings.xml")
In any case, you need to decide, whether you want to search configuration file using absolute path, or path relative to current directory/installation directory/executable directory. The code, installation package and execution command should be changed accordingly.

Categories

Resources