one Problem description: write an application to realize programmed teaching, the application must be completed by the function:
? Questions to the students;
? Have the answer from the student affairs office;
? According to the student the answer to continue to choose the next question,
two In the application of profile design, considering from the following aspects:
? How to say in your program programmed teaching course information needed? At the design stage, the need to develop a suitable data structure, it can be recorded and array combination,
? What is the course of the format of the data file? (data file by the courses taught by the teacher to edit operation rather than a programmer)
? How to convert data file using external said to internal representation?
? How to write a program to the database to operate?
3. Problem: the framework of
Program runs the basic operation steps are as follows:
? Put forward the current problem: a problem can have one or more lines of text, the text string representation can be used;
? To get the answer from the student affairs office: the answer can also by the string representation,
? Check for the problem of answer: if a student answers are listed in the above answer, reference data structure to choose new problems, if the student answers and provide the answer to the discrepancy, told students results and provide another opportunity to answer the question,
Four. The representation of a data
In order to make the application has a good portability, all the information about a certain course must be deposited in a data file, rather than write them directly to the program, program's mission is to read the data files, processes the information stored in the structure in the internal data structure, the process of designing the data structure includes two steps:
? First, you need to design a program to use, the internal structure of the internal data structure is composed of custom structure type definition, which is a combination of arrays and records, which can reflect the real world of information,
? Second, the need to design can reflect the external structure of data file information how to store,
These two steps are closely related, mainly because they represent the same information, but the two kinds of structure is designed for different purposes, the internal structure should facilitate programmers use, and external structure need service for curriculum designers, not too many difficulties in program operation,
(a) design internal representation
To design a data structure contains the necessary information, using the top-down approach starting at the top of the structure design, then details and gradually perfect, there is an important concept in database design - packaging: combine the information in the structure, and as a whole, for a large database of encapsulation process have layers, and must consider details at every level, in the top, it is necessary to take into account the entire database as a variable, it contains all the required information, as shown in the figure below, the database is expressed as pointer to a structure, the structure of the content for later consideration, when you need to transfer the entire database to a function, you only need to pass variables db can, this is a pointer, easy to operate it can be used to access other data, only when the function need to manipulate individual members in a database, only need to look at the details of the structure,
CodePudding user response:
This,,, the test or homework,,,
CodePudding user response:
This was what I want to do a project, a problem solving project, cross-platform, wanted to make it, because it is difficult to choose according to data controls to cross-platform and maintenance, so was shelved, then determine the best data file is the HTML files, text, images, forms, buttons, input fields, checkboxes, etc is very comprehensive, it is not the best choice of the two, if only to PC system is very simple, the program can directly and display control or CppWebBrowser WebBrowser control connection, write and modify is very flexible, cross-platform theoretically possible but technically difficult,