ICT209 Data Structures and Abstractions Using Visual C++ Version 6

Transcription

1 ICT209 Data Structures and Abstractions Using Visual C++ Version 6 Files required Visual Studio V6, Vs6sp6.exe, STRING Basic Information We will be using Visual C++ V6, this is available on all lab computers and is free to students. Internal students should have received an at the start of week 1 giving them instructions on how to download the program. Please make sure you follow the instructions exactly. If you did not receive the then you need to contact Danny Toohey (d.toohey@murdoch.edu.au) giving him your student number and address and unit and asking him to add you to the list. External students should have received the program on disk prior to the start of semester. If you do not then you must contact your unit coordinator Nicola Ritter (n.ritter@murdoch.edu.au) as soon as possible. After installing VC++ V6 and the MSDN help pages (if available), you must download Service Pack 6 (Vs6sp6.exe) from WebCT or on disk to external students. After installing SP6, you need to download the STRING header file from WebCT. This file must replace the one in SP6 (which has a bug). Assuming you follow the default settings, this file needs to go in C:\Program Files\Microsoft Visual Studio\VC98\Include. VC++ uses workspaces to link sets of programs. It stores this information in a set of three files:.dsw,.ncb and.opt. Within each workspace you can have multiple projects. A project is a set of files that can be compiled as a single entity. Project files have a.prj extension and are stored in directories underneath the workspace directory. For your project you will be using one workspace with multiple projects. 1

2 Finding Help The help files in VC++ are useful if you are using VC++ as Microsoft intended: as a Visual programming language. However if you are using VC++ to write console programs in ANSI standard C++, they are lacking. Google turns out to be far better at finding help than VC++. For example, should you forget how to specify a column width in C++, then searching for setting widths in C++ in the VC++ help pages gets you 44 topics, none of which are useful. However typing this into Google gets you over 1 million pages, the first four of which give exactly the information you need. Finally, if you already know the name of a function, but have just forgotten the syntax, typing man followed by the function name into Google will get you manual pages about the function. For example man setw gets you manual pages (full details, plus examples) about the setw function. Note: to get help from your tutor, you must have your code formatted correctly! Setting up VC Open Visual Studio Before anything else, check that options are set correctly within VC++: (a) Choose Tools-Options. (b) Under the Editor tab you should see Save options. (c) Make sure that Save before running tools is selected. (d) Under the Tabs tab, make sure that the tab size and indent size are both set to 4 and that the Keep tabs option is chosen. (e) Under the Format tab, go to the box labelled Colors and select String, then go to the Foreground box underneath and choose Magenta. (f) Press [OK] to close the dialog box. 2

3 Creating a New Workspace 1. Create a directory in your home area and call it ICT209 Code. 2. Underneath this create a directory called Code. 3. Open VC Creating a new workspace: (a) Choose File-New or press <Ctrl>-N, this will produce a pop-menu with TABS giving you choices for creating new Files, Projects, Workspaces or Other Documents. (b) Click on the Workspaces tab. (c) On the right hand side of the dialog box you should see an edit box labelled Location. In this edit box you should type the path and name of the directory created in 2 above. Alternately you can use the browse button to find it. (d) In the edit box above this labelled Workspace name type in the workspace name. For example Project. (e) Click [OK] to close the dialog box. (f) On the left hand of the VC++ dialog box you should see a pair of tab frames labelled (at the bottom) with [ClassView] and [FileView]. Choose the [FileView] tab and you will see a tree of the workspace. At this point, of course, it will just give the name of the workspace plus the fact that it contains 0 projects. Adding a New Project to a Workspace 1. Open the New dialog box again as described above, or right click on the name of the Workspace in the [FileView] pane on the left and choose [Add New Project to Workspace]. 2. This time you need the Projects tab. 3. On the right hand side of this dialog box you will see radio buttons giving you the choice of Create new workspace or Add to current workspace. We want to add the project to the current workspace, so choose that option. 4. In the edit box Project name type in the name of the project, which will almost always be the name of the class that you are creating and testing in this project. 5. Next you need to select the type of project on the left hand side panel. All projects in this unit will be Win32 Console Applications, so choose that option. 6. Click [OK] to close the dialog box. 7. You will now see a dialog box asking you What kind of Console Application do you want to create?. Always choose An empty project. If you don t then Microsoft adds in all sorts of extra code that you do not want! 8. Click [Finish] to close that dialog box and [OK] to close the next. 9. In the left hand [FileView] pane, you should now see that the workspace has one project with the name you provided. If you open that project you will see three pseudo-folders (they are not real folders) labelled Source Files, Header Files and Resource Files. The folders are all empty, of course. 3

4 Adding an Existing Project to a Workspace 1. Write click on the name of the Workspace in the [FileView] tab on the left. 2. Choose [Insert Project into Workspace]. Adding a New File to a Project 1. Open the New dialog box again. 2. This time you need the Files tab. 3. In the left hand pane choose C++ Source File. 4. On the right type in a file name, for example: first.cpp. 5. Click [OK] to exit the dialog box. 6. In the [FileView] pane on the left, you can now expand Source Files under which you should see the name of your new file. 7. You will also, perhaps, have noticed that the main part of the program is now white: you have a blank file in which to start typing. Adding an Existing File to a Project 1. Right click on the name of the project. 2. Choose [Add Files to Project], browse to select the files. 3. Note that you can also copy and paste within the [FileView] tree structure in the left hand pane. Selecting the Active Project The active project is the one that is compiled when you press the compile quick key (see below). 1. Right click on the name of the Project. 2. Choose [Set as Active Project]. 4

5 Compiling and Running 1. <Ctrl>-<F7> compiles the currently open (selected) file. 2. <F7> compiles the whole project. 3. <Ctrl>-<F5> compiles and runs the program in non-debug mode. This means that the output console will remain open when the program finishes, allowing you to view your output. 4. <F5> compiles and runs the program in debug mode. This means that you can run the program to a break point. Note however that when the program finishes, the output console is automatically closed. 5. If your program compiles successfully, then in the output pane (at the bottom of the screen) you should see something like: Configuration: Compiling... FileName.cpp Linking... ProjectName - Win32 Debug ProjectName.exe - 0 error(s), 0 warning(s) 6. If your program did not compile successfully, then you will see warning and/or error messages. 7. If you have any warnings or errors, pressing <F4> will take you directly the the first error. 8. Note that all programs must compile with no warnings. 5

6 Debugging 1. <F9> will set a break point in the code. A break point is a point at which execution will stop allowing you to step through the code. 2. <F10> will step through the current function one line of code at a time. If the line of code is a function call, then it executes the whole of the function call. 3. <F11> will step through the current function one line of code at a time. If the line of code is a function call, then it jumps to that function and continues to execute one line at a time. 4. <Shift>-<F11> completes the execution of a function and jumps back to the calling function. 5. While stepping through the code, the current value of a variable can be viewed by moving the hovering the mouse cursor over it. 6. However this is only useful for simple types like int and float. 7. To view the value of an object: (a) Right click on the variable identifier you want to watch. (b) Choose [Quick Watch], this opens a tree view of the object. (c) Open parts of the object by pressing appropriate [+] buttons in the tree view. (d) If you want to keep watching the object click the [Add Watch] button. (e) You will now see the identifier in the Watch Window at the bottom right of Visual C Note that it is often easier to output the OutputString() of an object rather than use the watch window. 6

7 Formatting Output The following table gives the most useful formatting commands, plus examples. Note that num1 = 59 and num2 = for each example. Further information can be found in your text book. Name Description Applies Examples Output setw Sets column width once only cout << setw(5) << num1 << endl << num1; setfill Sets a fill character for the column space on the right of the actual output cout << setfill( 0 ) << setw(5) << num1; left Left justifies all output cout << left << setw(5) << num1; right Right justifies all output hex Outputs in hexadecimal cout << "0x" << num1; 3b oct Outputs in octal cout << "0" << num1; 73 dec setprecision Outputs in decimal integer (resets to normal output) Sets the number of significant figures (digits) fixed Forces precision to act on the number of decimal places only. If precision has not been set then the default is 6 decimal places cout << setprecision(3) << num2; cout << fixed << num2; cout << setprecision(3) << fixed << num2;