Oct 7, 2015 · There are no differences in terms of the state of the objects following your two snippets. Why are there two versions? The ctor exists in order to create fstream objects that are immediately associated with a stream. The open exists …

Mar 28, 2019 · When opening a file, it's preferable to use open() instead of invoking the file constructor directly. The reason is that in future versions they is not guaranteed to be the same ( open will become a factory function, which returns objects of different types depending on the path it's opening).

What is the difference between opening a file with a constructor function and opening a file with open () function? When is one method preferred over the other? When we open a file with a constructor a file name must be supplied during creation of object. Example : ofstream outfile (“result”); //output only.

Dec 4, 2019 · From programming point of view, there is no difference between opening a file with constructor function and opening a file with open () function, It is mainly related to the style or format the programmer is using throughout the program.

Jul 17, 2019 · Constructors of the stream classes ifstream, ofstream and fstream are used to initialize the file stream object with the file name. For example , ifstream read_file(“Names.Dat”); (b) Using the function open() - This method is useful when …

Nov 18, 2022 · A file can be opened in two ways: (i) using constructor function of a class. (ii) using the member function open ( ) of the class. Opening a file using constructor function:- The following...

Jun 12, 2022 · The syntax is as follows: file-stream-class stream-object; stream-object.open(“filename”); The basic difference between the two methods is that the constructor function of the class is used when we wish to open just one file in the stream.

Programming in C++ – Opening Files using Constructor. While using constructor for opening files,filename is used to initialize the file stream object. This involves the following steps. Create a file stream object to manage the stream using the appropriate class i.e the class ofstream is used to create the output stream and the class ifstream to

datafile. Let us learn how to open a file. 21.1.1 Opening a file A file can be opened in two ways: (i) using constructor function of a class. (ii) using the member function open ( ) of the class. Opening a file using constructor function The following statement opens the file STU.DAT in output mode, i.e., for writing data on the file.

Sep 11, 2024 · The member functions belonging to fstream class are constructor, open, is_open, close, and inherits get(), getline(), read(), seekg() and tellg() from istream, inherits put(), write() seekp() and tellp() from ostream.