Programming with Visual C++: Concepts and Projects Chapter 2B: Reading, Processing and Displaying Data (Tutorial)

Programming with Visual C++: Concepts and Projects

Chapter 2B:Reading, Processing and Displaying Data

(Tutorial)

Tutorial: Addition Program• Problem Analysis– Create an addition program for double precision

numbers• Design– Sketch the interface– Identify required controls for input, processing

and output– Identify the variables to store two numbers and

their sum– Construct an algorithm for input, processing and

output


Tutorial: Addition Program

• Development– Create the interface– Code the event handlers

• Testing


Design


• Interface sketch– Position each control object on the form as it

should look in the finished product– Name each control object

Design (continued)


Design (continued)


• Control table – List the control objects from the interface sketch – Identify their usage (input, processing, output) – List any events associated with them

Design (continued)


• Data Table– Identify variables that will be required, by name– Assign a data type to each variable (double in this case)– Describe the purpose of the variable

Design (continued)

• After the interface has been designed algorithms must be written for each event handler

• This program has a button• The button has a click event handler requiring

an algorithm


Design (continued)

• Algorithm1. Declare variables2. Read num13. Read num24. Compute sum5. Display sum


Development


• Create the actual interface based on the preliminary sketch you did in the Design stage– Place control objects on the form– Set the properties of these objects

Development (continued)







• The Development stage is where the code must be written for each event handler

• Before writing any Visual C++ code you must have a plan (an low-level algorithm)

• Ideally, from each line of the algorithm a Visual C++ statement can be constructed







• Comments should be added to your code at regular intervals

• Comments are ignored by the compiler• Comment syntax– Line comment

• Used for one line, or a portion of a line• //

– Block comment• Used for multiple lines of comments• /* … */




Testing

• Run the program and enter various numbers into the Textboxes– Check the displayed result for accuracy


Testing (continued)


On Your Own

• Modify the interface– Rearrange the control objects

• Add more operations– Implement addition, subtraction, multiplication

and division– Additional buttons are required for each operation


On Your Own (continued)


On Your Own (continued)


Programming with Visual C++: Concepts and Projects Chapter 2B: Reading, Processing and Displaying Data (Tutorial)

Documents

visual c code

visual c statement

projectsdesign continuedafter

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