online test system

1. Project Introduction

​ This project is an online examination system for JavaWeb. Users can register, log in, answer questions online, and view historical records. At present, there are only single-choice questions. In the future, if you have time and energy, you can expand multiple-choice questions and short-answer questions... (This project is the result of phased learning, and the function is relatively simple)

Second, the technology used

Development tools: IntelliJ IDEA 2018.3.5

Operating system: win10 professional edition

Language used: Java

Front-end framework: layui

Background framework: Spring Data Jpa, Spring Boot, Mybatis

Database: MySQL 5.7

3. Examination process:

1. User front desk registration
2. Administrator background login, add exams, add questions, publish exams
3. Candidates log in to the front desk to take the test and hand in the paper
4. The system automatically compares the answers
5. Candidates can view their scores in the exam history

4. Part of the interface

1. Front desk

answer questions

Exam History

2. Backstage

Exam paper management

History test paper management

Five, database table

1.user table

field name	Types of	primary key	is empty	describe
id	int	Yes	no	primary key ID
name	varchar(20)	no	no	Name
email	varchar(50)	no	no	Mail
password	varchar(20)	no	no	password

2. Question table question

field name	Types of	primary key	is empty	describe
id	int	Yes	no	primary key ID
content	varchar(1000)	no	no	stem
to	varchar(200)	no	no	A option
sb	varchar(200)	no	no	B option
sc	varchar(200)	no	no	option C
sd	varchar(200)	no	no	D option
answer	char	no	no	Answer
pid	int	no	no	Paper ID

3. Exam paper

field name	Types of	primary key	is empty	describe
id	int	Yes	no	primary key ID
pname	varchar(20)	no	no	paper name

4. History test paper sheet

field name	Types of	primary key	is empty	describe
id	int	Yes	no	primary key ID
papername	varchar(20)	no	no	paper name
userid	int	no	no	User ID
time	datetime	no	no	Question time
on one	int	no	no	Fraction
username	varchar(20)	no	no	username

5. History question sheet squestion

field name	Types of	primary key	is empty	describe
id	int	Yes	no	primary key ID
answer	char	no	no	correct answer
doanswer	char	no	no	Respondent's answer
to	varchar(200)	no	no	A option
sb	varchar(200)	no	no	B option
sc	varchar(200)	no	no	option C
sd	varchar(200)	no	no	D option
spid	int	no	no	History paper ID
content	varchar(1000)	no	no	stem

6. Administrator table admin

field name	Types of	primary key	is empty	describe
id	int	Yes	no	primary key ID
email	varchar(20)	no	no	Mail
password	varchar(50)	no	no	password
name	varchar(20)	no	no	Name

6. Knowledge summary

1. The frontend uploads the json array, and the backend SpringBoot accepts the method.

The frontend first uses JSON.stringify() to [parse a string from an object], upload it to the backend, and after the backend accepts the string, use Google's Gson.jar to convert from json to list.

//json转换为list
Gson gson = new Gson();  
List<Person> persons = gson.fromJson(str, new TypeToken<List<Person>>(){
    
    }.getType());

//list转换为json
Gson gson = new Gson();  
List<Person> persons = new ArrayList<Person>();  
String str = gson.toJson(persons);  

front desk

var q = JSON.stringify(questions)
$.ajax({
    
    
    type:"post",
    url:'insSquestion',
    data:{
    
    questions:q},
    success:function (res) {
    
    
        if (res > 0){
    
    
            alert('提交成功')
            window.location.href="index"
        }
    }
})

Backstage

@RequestMapping(value="insSquestion")
    public int insSquestion(String questions){
    
    
        Gson gson = new Gson();
        List<Squestion> qs = gson.fromJson(questions, new TypeToken<List<Squestion>>() {
    
    }.getType());
        return squestionServiceImpl.insSquestions(qs);
    }

2. The use of the time plugin jquery.countdown.js

1. Introduce jquery and jquery.countdown.js into the page.

2. You can pass a string of valid time

<div>12:30</div>
<div>12:30:39</div>
<div>12:30:39.929</div>

3. After the page DOM elements are loaded, countDown()the countdown plug-in can be initialized through a method.

$('div, h1, time').countDown();      

4. Events

time.elapsed: This event is triggered immediately when the countdown ends.

$('#my-countdown').on('time.elapsed', function () {
    
    
    // do something...
}); 

7. Disadvantages

1. The database design is unreasonable. Due to the unfamiliarity with Spring Data Jpa's linked table query, repeated fields appear in the database design.

2. Single function, only multiple choice questions.

Github:https://github.com/zXiaoHuiYang/exam