1 ENG236: ENG236: C++ Programming Environment (2) Rocky K. C. Chang THE HONG KONG POLYTECHNIC UNIVERSITY

2 Programming Environment Before doing any C++ programming, first we need to familiarize with the programming environment. A programming environment is a software package that can help us develop and test program codes. For PC, one of the most popular programming environments is Microsoft Visual Studio. It is more popular because of its direct support to the Microsoft Windows environment. Computer Programming and Basic Software Engineering 2. A Taste of C++

3 Computer Programming and Basic Software Engineering 2. A Taste of C++ Visual C++ is one of the components of the umbrella product – Visual Studio, which also contains development tools for other programming languages, e.g. Visual Basic, Visual J++, etc. Visual Studio has been for sale for more than 10 years. The latest version is Visual Studio.NET. The C++ compiler that is incorporated is Visual C++.NET. Additional features include Produce managed codes that run in the.NET runtime Allow the use of.NET class library. Visual Studio.NET Second semester

4 Visual Studio – Solution and Project In Visual Studio, each user task is referred to as a solution to a problem. A solution refers to the computer resource (such as memory, disk space, etc.) required for one or more projects to complete the task. Every project contains executable code and debug information files containing the C++ programs classes and objects used in the project other related resources such as icon images used in the project graphical user interface (GUI), e.g. button, menu. Computer Programming and Basic Software Engineering 2. A Taste of C++ They are all in files

5 Computer Programming and Basic Software Engineering 2. A Taste of C++ Solution Project 1 Project 2 Project 3 Files A Solution must contain at least one Project A Project must contain at least one File

6 Source Program Editing Display compilation results Display resources of the solution, such as, projects and files inside Computer Programming and Basic Software Engineering 2. A Taste of C++

7 Visual Studio - Project Example Solution Explorer allows us to clearly see the different files included in the project Computer Programming and Basic Software Engineering 2. A Taste of C++

8 Visual Studio - Project Example Program can be typed here Computer Programming and Basic Software Engineering 2. A Taste of C++ Built result (result of compiling and linking) shown here

9 Build your first project - HelloWorld Building a project means to produce target executable files (.exe files) based on the program codes. Project can be built to execute in console or windows mode Console mode: Use the Command Prompt for in/output Windows mode: Use the Windows environment for program execution. Computer Programming and Basic Software Engineering 2. A Taste of C++ Second semester

10 Computer Programming and Basic Software Engineering 2. A Taste of C++ Command Prompt It is a traditional interface between the user and computer User types in commands to instruct computer to work.

11 Build your first project - HelloWorld #include int main() { std::cout << "Hello World!" << std::endl; return 0; } Hello.cpp : File containing a C++ program that prints a message “Hello World!” on the console output. Computer Programming and Basic Software Engineering 2. A Taste of C++ The returned type of main() must be declared in Visual Studio.NET 2005

12 Computer Programming and Basic Software Engineering 2. A Taste of C++ Step 1: Start the Visual Studio.NET 2005 Click New Project

13 Computer Programming and Basic Software Engineering 2. A Taste of C++ Step 2 Note where you create this project You can modify the location of the files of your project.

14 Computer Programming and Basic Software Engineering 2. A Taste of C++ Step 3

15 Computer Programming and Basic Software Engineering 2. A Taste of C++ Step 4: Right-click Source Files, select Add → New Item

16 Computer Programming and Basic Software Engineering 2. A Taste of C++ Step 5: Choose C++ File (.cpp). Give a name to the C++ file you are going to add

17 Computer Programming and Basic Software Engineering 2. A Taste of C++ Step 6: Type the program on p.11 here. Click Build → Build Solution See the built result

18 Computer Programming and Basic Software Engineering 2. A Taste of C++ Do you see the following result? Note: The result is shown in the Command Prompt – Console Application Step 7: Execute the program by clicking Debug → Start Without Debugging

19 Computer Programming and Basic Software Engineering 2. A Taste of C++ What has actually done? In the HelloWorld example, one solution is created that contains a project called chap2p1. Inside the project, there is one C++ program called Hello.cpp. Solution Project: chap2p1 C++ File: Hello.cpp

20 Computer Programming and Basic Software Engineering 2. A Taste of C++ The C++ Compiler of Visual Studio compiles the program Hello.cpp and generates an executable file chap2p1.exe. When you click Debug → Start Without Debugging, Visual Studio actually runs the executable file chap2p1.exe for you. All files generated in this project is stored in C:\Documents and Settings\Administrator\My Documents\Visual Studio 2005\Projects\chap2p1 Run Windows Explorer

21 2. A Taste of C++ Computer Programming and Basic Software Engineering Contains all files created after building the solution Contains info. about the project. Double-click this will automatically start the project The C++ file you created

22 Computer Programming and Basic Software Engineering 2. A Taste of C++ The EXE (executable) file created

23 Computer Programming and Basic Software Engineering 2. A Taste of C++ We can always run the program under the command prompt

24 Exercise 2.1 Consider the two programs on the RHS. For each of the program, construct a new project in Visual Studio and then build the solution. For each program, note the error messages when building the project. Fix the errors and execute the resulting project. What do you see? #include int main() cout << "Hi World!" << std::endl; return 0; } #include int test() { std::cout << "How are you!" << std::endl; return 0; } Computer Programming and Basic Software Engineering 2. A Taste of C++

25 Exercise Open the Command Prompt. 2.By using the command cd, change the current folder to the folder that contains chap2p1.exe (you may want to use the command dir to show the content of a folder.) 3.Run chap2p1.exe by typing its file name and press Enter. 4.Compare the result with that you run the program in Visual Studio. Can you see any difference coming up? 5.If no, add the following lines of code before “ return 0 ;” of Hello.cpp. std::cout<<"Press Enter to continue."<<std::endl; std::cin.get(); Rebuild the solution. Repeat 1 to 4 and note any difference. Computer Programming and Basic Software Engineering 2. A Taste of C++

26 Acknowledgment The slides are based on the set developed by Dr. Frank Leung (EIE).