I am a beginner in visual studio and has only code C and C++ in command line settings.
Currently, I am taking a module(software development) which requires me to come up with an expense tracker - a program which helps user tracks his/her daily expenses. Therefore, at the end of each individual day, or after a user uses finishes the program, we would have to perform data storage to store all the info in one place which we would export it during the next usage.
My constraint include not using any relational database(although i have no idea what it is :( ). Data storage must be done using XML or text files. Following this, I have several questions regarding data storage:
1) If data is stored successfully, do we export it everytime we start the program? And everytime after the user closes the program, we overwrite the existing data file and then store it accordingly?
2) I have heard from some people that using text file may be easier. Searching on the internet and library only provides me with information regarding XML and not text. Would anyone be able to help me with it? Like tutorials link and stuff?
Thank you very much!
File writing/handling works similar to every other buffer in c++.
you can enable file handling using the fstream header. You can create a file, write to it and over-write every time the program is run, or can even create a file the first time the program is run and then append to it every subsequent time the program runs.
Ive only ever done text files, never tried XML, but Im guessing they're similar.
http://www.cplusplus.com/doc/tutorial/files/ should give you everything you need to know.
Your choice of XML vs plain text depends on the kind of data that you'll be storing.
The reason why you'll only find XML libraries on the internet is because XML is a lot more complicated than plain text. If you don't know what XML is or if the data that you're storing isn't very complex, then I would suggest going with plain text.
For example, to track expenses, you might store a file like this:
sandwich 5.00
coffee 2.30
soft drink 1.50
...
It's very easy to read/write lines like this to/from a file in C++.
Related
I'm making a desktop app with wxWidgets but I can't figure out how it can have a more complex save system. For example, a project in Sony Vegas is saved in one file, and it's a (.veg). My save system will have to save mostly text from user, but in different areas. To be able to do this, do I need to save each thing I need separatly and load them all when I wish to re-enter the app? Sorry if this question seems obvious, I'm new fairly new at using wxWidgets.
Saving data to one or more files depends on how you organize your app.
It may read data from a file only when needed. Different tasks may use different files.
It may store everything in a single file. Read it all once. Or read parts of it for different tasks. If the file is too much big (my opinion, greater than 50 MB), obviously this is not the best option.
For the second option you may use std <fstream> functions. Or some of those provided by wxWidgets, which you will appreciate if you need to deal with text encodings, or other features as well.
Also, wxFileConfig may be useful if you wish to set several "sections" of your data.
I am from Slovakia, I wouldn't be surprised if most of you haven't heard about it.
However, that causes me a troubles when it comes to reports. We need to have 3 (soon 4) language versions of each report: Slovak is main language, than, Polish and English.
Since pentaho does not support Polish nor Slovak, it is really pain for me to keep these localized.
What I do is:
Create report in Slovak language
Write down all phrases from report
Send phrases to one of our partners to translate
Create its copy in either pl/en directory
Open it in Report Designer and edit every phrase accordingly
Save as another language version
As you can imagine, the process is very time consuming, and error prone. Plus, every time I add new parameter to report or change its data source (which is BeanShell script), I need to do it in 3 separated files. As a result of this, language mutations are usually out of date, way behind main language version.
I have tried to automate it with OneSky and did a python script that does 2 stages:
Stage 1 (extract and upload):
Change *.prpt files sufix to *.zip
Extract phrases from files: ~/datadefinition.xml, ~/layout.xml, ~/styles.xml, ~/datasources/inline-ds.xml
Put those phrases into *.po file
Export *.po file into OneSky
Stage 2 (download and import):
Change *.prpt files sufix to *.zip
Download translated *.po file from OneSky
Run through ~/datadefinition.xml, ~/layout.xml, ~/styles.xml, ~/datasources/inline-ds.xml files and replace original phrases by translated
While this aproach works fine, it doe not translate everything. There are still flaws of this process. I need to go through it every time I do even slightest change in data source of report or fix small mistakes. Even if I just do a small six in SQL code, I need to do it in 3 files. That of course increases chance to mistake be made.
Soo, I was wondering, how are you guys solving this issue with translating of your reports?
I will share very simple method which we are following.
1)create a properties file with key value format for each language for resource labels(for static values)
2)put it into resources folder(report-designer/resources/)
3)Based on the parameter you can specify which properties file to select and you can specify keys into value field so that it can understand which value to display in which language.
4)if you need to convert the data which are coming from database,you have to design data warehouse specify all the mappings,accordingly it can fetch the data.
5)For converting dates and currency symbols or number format you can use inbuilt functions which can handle all this things,i am using mysql and mysql has translation functions which can handle all such things.
it is difficult to explain entire process here, but if you can get and idea from this it can be useful to you.
I m writing a c++ program using files and i need to take the input from existing files such as doc files and pdf files. how to program it in c++? And after getting the inputs, how can i write those details into a new doc or pdf files? Can anyone explain me with an example?
C++ as a language doesn't equip you with such features as "write to DOC file" or "read from PDF file". The only staff available to you a a programmer is raw byte-by-byte reading or writing. To make your new brand file as PDF/DOC/etc compatible you have to conform the chosen file format. The same about reading - you should understand which portions of raw byte array are responsible for what.
In common, this task named as "parsing" or "serialization". And it's a good idea to use one of existing parsers for particular file format instead of reinventing the wheel. Moreover, some file formats can be patent-pending so you may be not allowed to deal with it without license purchase.
Some clues so far:
PDF parsing in C++ (PoDoFo)
Microsoft word Text Parser in "C"
There are some libraries available on the web now(the question is from 2013, maybe that time there weren't many).
Apart from the links in selected answer, you can try PDFTron. It also supports new features, eg. Linearization.
Here is one of their samples is ->
https://www.pdftron.com/documentation/samples/cpp/TextExtractTest
(That program itself contains 4 if blocks, with slightly different features of the library/SDK, to try)
There should be more, search on the web for PDF parsing libraries.
I'm writing a C++ MFC program, and I see programs that remember the last input values for some fields from one program run to the next. I could do this by saving it to a file and loading that and then repopulating, but is there another, quicker way of doing this, as I think I remember reading somewhere that these values could be stored in the registry? If anyone has an example or personal experiences, I would be very interested.
Thanks,
James
There are many options out there
I personally don't like the registery and prefer to keep my program portable.
so what I can think of right now are
1- ini files
2- property files
3- SQL server
4- you can also synchronize the user settings via web server, but as #Jeeva mentioned there are security considerations
Cheers
It all depends on what kind of values you want remember. If it is an configuration data you can use config files. If it is small application data you can use flat files with proprietary format. If it is huge data you can use a database like SQL Server.
Usually there is a debate about using ini file vs registry.
Other things you want to consider is whether the data will be used across network. Whether you need to encrypt.
I've seen a lot of games use something similar to a .DAT file or a specific file type that the game has for itself. I'm just beginning with C++ and DirectX and I was interested in keeping my information in something similar to a .DAT.
My initial conception was that it would hold information on the files you wanted to store within the .DAT file. Something similar to a .RAR file. Unfortunately, my googleing skills did not help me in finding the answers.
Right now I'm simply loading textures and sound files from a folder called Data.
EDIT: While I understand that .DAT is short for data, and I've found that a .DAT file generally contains any assortment of information, I'm still unsure about how to go about doing something as packing images and sound files into any type of file and being able to read them.
I'm not sure about using fstreams to achieve my task, however I will look into streams related to storing data and how to properly read from that data. Meanwhile if anyone has another answer to offer based on this new information, it would be appreciated.
EDIT: Thanks to the answers, I stumbled across a similar question on stackoverflow and felt I'd share it here. Combining resources into a single binary file
I don't think there is really such thing as .dat file format. It's short for "data," and different applications just put in some proprietary stuff in it and call it ".dat." You can read up on fstream classes to do file IO in C++. See Input/Output with files.
What you then do is make up your own file format. For example, first 4 byte is int that indicates the number of blocks in the .dat and for each block, you have 4 byte indicating the length of each block, 4 byte indicating the type of the block, the variable length data itself .. something like that.
DAT obviously stands for data, and there is no real or de facto standard on what that extension actually refers to. Your decisions on the best file formats should be based on technical considerations, not pointless attempts at security through obscurity.
Professional games use a technique where they put all the needed resources (models, textures, sounds, ai, config, etc) zipped/packed into a single file thus making it faster to manage, harder to change (some even make use of a virtual filing system from what's inside the data file). Now, for what's inside the file is different depending on the needs of the game and the data structures that you use.
If you're just starting into gamedev, i recommend you stick with keeping all you assets separate and don't bother too much about packing them into a single file.
Now if you really want to start using a packed format here's a good pointer:
Creating a PAK File Format
Here's a link which claims that .dat is a movie format, 'DAT' being short for Digital Audio Tape.
I'm not sure I believe the link, but I do remember something about a Microsoft supported format called DAT, from long ago, when I used an earlier version of Windows.
It makes more sense as a logical extension for a DATA file of some kind.
.dat, as others have said, is literally just a data file. In reality, the file extension means nothing other than association with a program. For example, I could make a word processor that saves all the documents with the .mp3 file extension. These files wouldn't be playable in any media software, but the software might try. File extensions are used to help programs know what types of files they can and cannot open--however those rules don't have to be followed.
Anyway, you can dump any sort of information to a file. Programmers/software writers will often choose .dat as the extension of that file because it has become the standard to signify 'this file just holds a ton of data' and that the data doesn't necessarily hold any standardized headers, footers, or formatting.
A dat file could really contain anything. It might be as simple as a zip archive with the extension changed, or it could be a completely custom file type. If you're just starting out, you probably don't want to write your own file format, although doing so can be fun and educational. If you want to encapsulate your data files into some kind of container, you should probably go with a zip, paq, or maybe tar.gz.