Example analysis of using JavaScript to generate lottery numbers
This "Lottery Number Generator" is purely front-end development, involving HTML, JS, and CSS. For the sake of simplicity, all the codes are written into an html file. The advantage of this is that the file can be opened directly with a browser. Of course, in actual work, it is best to put them in different files. The entire area is placed in a large p tag, which appears as a rectangular area, and the display position is controlled through JS; set up a drop-down list, and you can choose to generate 1-5 groups of random numbers. When the button is clicked , you can generate numbers corresponding to the number of groups; the number area is divided into two parts. The upper part is a randomly generated unordered number, and the lower part is a number after sorting these unordered numbers. The number of generated groups is controlled by the drop-down list above. The core of this tool is to generate random numbers and sort the random numbers, both of which are implemented through JS code. Here are some important JS codes.
Generate random numbers: Lotto is divided into front area numbers and rear area numbers. The front area numbers are 5 numbers from 01-35 without repetition, and the rear area numbers are from 01-12 without repetition. Take 2 numbers to form a set of 7-digit numbers. Two arrays are defined here: arr35 stores the 01-35 numbers in the front area, and arr12 stores the 01-12 numbers in the back area. Use the "temp = Math.floor(Math.random()*arr35.length)" method to take a random number from 0-arr35.length as the index, and use arr35[temp] to get the value of the index position in the array, also It is a random number, and then dynamically added to the span before sorting by getting the id. After fetching, use "arr35.splice(temp,1);" to delete the random number in the array and reduce the length of the array by one. Loop 5 times to get 5 random numbers from 01-35 without repetition, and the same goes for the next two digits.
var arr35 = ["01","02","03","04","05","06","07","08","09","10","11","12","13","14","15","16","17",
"18","19","20","21","22","23","24","25","26","27","28","29","30","31","32","33","34","35"];
var arr12 = ["01","02","03","04","05","06","07","08","09","10","11","12"];
var span = "";
var temp = "";
for(var i=1;i<6;i++){
span = "span" + x + i;
temp = Math.floor(Math.random()*arr35.length);//随机取一个数
document.getElementById(span).innerText = arr35[temp];
document.getElementById(span).style.backgroundColor = "red";
arr35.splice(temp,1);//删除该位置的值}Random number sorting: The insertion sort algorithm is used here, which only sorts the first five digits of each group of numbers. The amount of data is very small. After sorting, the id is dynamically added to the sorted span by obtaining the id.
//插入排序
function bubbleSort(array){
var len = array.length;
for (var i = 0; i < len; i++) {
for (var j = i; j > 0 && array[j]<array[j-1]; j--) {
var swap = array[j]; //第二个for循环使元素比较并移动到合适位置
array[j] = array[j-1];
array[j-1] = swap;
}
} return array;
}The remaining JS, HTML, and CSS technologies will not be introduced in detail.
Complete code:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>大乐透号码生成器</title>
<style type="text/css">
#table{
width:800px;
height:500px;
margin:10px;
border:2px
solid
#000000;
box-shadow: 10px 10px 5px;border-radius:50px;}
.buttonStyle{height:40px;margin:20px;font-size:20px;background-color:#6495ED;color:white;border-radius:10px;}
.oneStyle{margin-left:200px;margin-top:10px;font-family:sans-serif;font-size:20px;}
span{border-radius: 50%;color: #FFFFFF;padding:3px;font-size:13px;}
</style>
</head>
<body>
<p id="table">
<p>
<h1 id="大乐透号码生成器">大乐透号码生成器</h1>
</p>
<p class="oneStyle">
生成组数：<select id="zushu" style="width:150px;height:30px;margin:10px;" onchange="select()">
<option value="1">生成 1 组号码</option>
<option value="2">生成 2 组号码</option>
<option value="3">生成 3 组号码</option>
<option value="4">生成 4 组号码</option>
<option value="5">生成 5 组号码</option>
</select>
</p>
<p class="oneStyle">
随机号码1：<span id="span11"></span> <span id="span12"></span> <span id="span13"></span>
<span id="span14"></span> <span id="span15"></span>
<span id="span16"></span> <span id="span17"></span><br>
随机号码2：<span id="span21"></span> <span id="span22"></span> <span id="span23"></span>
<span id="span24"></span> <span id="span25"></span>
<span id="span26"></span> <span id="span27"></span><br>
随机号码3：<span id="span31"></span> <span id="span32"></span> <span id="span33"></span>
<span id="span34"></span> <span id="span35"></span>
<span id="span36"></span> <span id="span37"></span><br>
随机号码4：<span id="span41"></span> <span id="span42"></span> <span id="span43"></span>
<span id="span44"></span> <span id="span45"></span>
<span id="span46"></span> <span id="span47"></span><br>
随机号码5：<span id="span51"></span> <span id="span52"></span> <span id="span53"></span>
<span id="span54"></span> <span id="span55"></span>
<span id="span56"></span> <span id="span57"></span><br>
</p>
<p class="oneStyle">
排序后码1：<span id="span61"></span> <span id="span62"></span> <span id="span63"></span>
<span id="span64"></span> <span id="span65"></span>
<span id="span66"></span> <span id="span67"></span><br>
排序后码2：<span id="span71"></span> <span id="span72"></span> <span id="span73"></span>
<span id="span74"></span> <span id="span75"></span>
<span id="span76"></span> <span id="span77"></span><br>
排序后码3：<span id="span81"></span> <span id="span82"></span> <span id="span83"></span>
<span id="span84"></span> <span id="span85"></span>
<span id="span86"></span> <span id="span87"></span><br>
排序后码4：<span id="span91"></span> <span id="span92"></span> <span id="span93"></span>
<span id="span94"></span> <span id="span95"></span>
<span id="span96"></span> <span id="span97"></span><br>
排序后码5：<span id="span101"></span> <span id="span102"></span> <span id="span103"></span>
<span id="span104"></span> <span id="span105"></span>
<span id="span106"></span> <span id="span107"></span><br>
</p>
<p style="text-align:center">
<input class="buttonStyle" id="fiveNumber" type="button" onclick="number()">
</p>
</p>
<script type="text/javascript">
var table = document.getElementById("table");
var width = document.documentElement.clientWidth; //浏览器可见区域宽
var height = document.documentElement.clientHeight; //浏览器可见区域高
table.style.marginLeft = ((width-800)/2)+"px";
table.style.marginTop = ((height-700)/2)+"px";
var val = "1";
document.getElementById("fiveNumber").setAttribute("title","生成 1 组号码");
document.getElementById("fiveNumber").setAttribute("value","生成 1 组号码");
//随机生成五组号码
function select()
{
val = document.getElementById("zushu").value;
var des = "生成 " + val + " 组号码";
document.getElementById("fiveNumber").setAttribute("title",des);
document.getElementById("fiveNumber").setAttribute("value",des);
} //随机生成五组号码
function number()
{ for(var n=1;n<11;n++){
for(var m=1;m<8;m++){
var a = "span" + n + m;
document.getElementById(a).innerText = "";//每次点击按钮先清空上一次数据
document.getElementById(a).style.backgroundColor = "white";
}
} for(var x=1;x<(parseInt(val)+1);x++){ //从35个号码里面无放回地取5位
var arr35 = ["01","02","03","04","05","06","07","08","09","10","11","12","13","14","15","16","17",
"18","19","20","21","22","23","24","25","26","27","28","29","30","31","32","33","34","35"];
//从12个号码里面无放回地取2位
var arr12 = ["01","02","03","04","05","06","07","08","09","10","11","12"];
var span = "";
var temp = "";
for(var i=1;i<6;i++){
span = "span" + x + i;
temp = Math.floor(Math.random()*arr35.length);//随机取一个数
document.getElementById(span).innerText = arr35[temp];
document.getElementById(span).style.backgroundColor = "red";
arr35.splice(temp,1);//删除该位置的值
}
for(var j=6;j<8;j++){
span = "span" + x + j;
temp = Math.floor(Math.random()*arr12.length);//随机取一个数
document.getElementById(span).innerText = arr12[temp];
document.getElementById(span).style.backgroundColor = "blue";
arr12.splice(temp,1);//删除该位置的值
}
}
for(var x=1;x<(parseInt(val)+1);x++){
var span = ""; //前五位排序
var arr = new Array(5);
for(var y=0;y<5;y++){
span = "span" + x + (y+1);
arr[y] = document.getElementById(span).lastChild.nodeValue;
} var a = bubbleSort(arr);
for(var l=0;l<5;l++){
span = "span" + (x+5) + (l+1);
document.getElementById(span).innerText = a[l];
document.getElementById(span).style.backgroundColor = "red";
} //后两位排序
var spann6 = "span" + x + "6";
var spann7 = "span" + x + "7";
var spanm6 = "span" + (x+5) + "6";
var spanm7 = "span" + (x+5) + "7";
var span6 = document.getElementById(spann6).lastChild.nodeValue;
var span7 = document.getElementById(spann7).lastChild.nodeValue;
if(parseInt(span6) > parseInt(span7)){
document.getElementById(spanm6).innerText = span7;
document.getElementById(spanm7).innerText = span6;
}else{
document.getElementById(spanm6).innerText = span6;
document.getElementById(spanm7).innerText = span7;
}
document.getElementById(spanm6).style.backgroundColor = "blue";
document.getElementById(spanm7).style.backgroundColor = "blue";
}
} //插入排序
function bubbleSort(array){
var len = array.length;
for (var i = 0; i < len; i++) {
for (var j = i; j > 0 && array[j]<array[j-1]; j--) {
var swap = array[j]; //第二个for循环使元素比较并移动到合适位置
array[j] = array[j-1];
array[j-1] = swap;
}
} return array;
} </script></body></html>Browser opening effect:
# #
The above is the detailed content of Example analysis of using JavaScript to generate lottery numbers. For more information, please follow other related articles on the PHP Chinese website!
Python vs. JavaScript: Development Environments and ToolsApr 26, 2025 am 12:09 AMBoth Python and JavaScript's choices in development environments are important. 1) Python's development environment includes PyCharm, JupyterNotebook and Anaconda, which are suitable for data science and rapid prototyping. 2) The development environment of JavaScript includes Node.js, VSCode and Webpack, which are suitable for front-end and back-end development. Choosing the right tools according to project needs can improve development efficiency and project success rate.
Is JavaScript Written in C? Examining the EvidenceApr 25, 2025 am 12:15 AMYes, the engine core of JavaScript is written in C. 1) The C language provides efficient performance and underlying control, which is suitable for the development of JavaScript engine. 2) Taking the V8 engine as an example, its core is written in C, combining the efficiency and object-oriented characteristics of C. 3) The working principle of the JavaScript engine includes parsing, compiling and execution, and the C language plays a key role in these processes.
JavaScript's Role: Making the Web Interactive and DynamicApr 24, 2025 am 12:12 AMJavaScript is at the heart of modern websites because it enhances the interactivity and dynamicity of web pages. 1) It allows to change content without refreshing the page, 2) manipulate web pages through DOMAPI, 3) support complex interactive effects such as animation and drag-and-drop, 4) optimize performance and best practices to improve user experience.
C and JavaScript: The Connection ExplainedApr 23, 2025 am 12:07 AMC and JavaScript achieve interoperability through WebAssembly. 1) C code is compiled into WebAssembly module and introduced into JavaScript environment to enhance computing power. 2) In game development, C handles physics engines and graphics rendering, and JavaScript is responsible for game logic and user interface.
From Websites to Apps: The Diverse Applications of JavaScriptApr 22, 2025 am 12:02 AMJavaScript is widely used in websites, mobile applications, desktop applications and server-side programming. 1) In website development, JavaScript operates DOM together with HTML and CSS to achieve dynamic effects and supports frameworks such as jQuery and React. 2) Through ReactNative and Ionic, JavaScript is used to develop cross-platform mobile applications. 3) The Electron framework enables JavaScript to build desktop applications. 4) Node.js allows JavaScript to run on the server side and supports high concurrent requests.
Python vs. JavaScript: Use Cases and Applications ComparedApr 21, 2025 am 12:01 AMPython is more suitable for data science and automation, while JavaScript is more suitable for front-end and full-stack development. 1. Python performs well in data science and machine learning, using libraries such as NumPy and Pandas for data processing and modeling. 2. Python is concise and efficient in automation and scripting. 3. JavaScript is indispensable in front-end development and is used to build dynamic web pages and single-page applications. 4. JavaScript plays a role in back-end development through Node.js and supports full-stack development.
The Role of C/C in JavaScript Interpreters and CompilersApr 20, 2025 am 12:01 AMC and C play a vital role in the JavaScript engine, mainly used to implement interpreters and JIT compilers. 1) C is used to parse JavaScript source code and generate an abstract syntax tree. 2) C is responsible for generating and executing bytecode. 3) C implements the JIT compiler, optimizes and compiles hot-spot code at runtime, and significantly improves the execution efficiency of JavaScript.
JavaScript in Action: Real-World Examples and ProjectsApr 19, 2025 am 12:13 AMJavaScript's application in the real world includes front-end and back-end development. 1) Display front-end applications by building a TODO list application, involving DOM operations and event processing. 2) Build RESTfulAPI through Node.js and Express to demonstrate back-end applications.
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
VSCode Windows 64-bit Download
A free and powerful IDE editor launched by Microsoft
DVWA
Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software
Atom editor mac version download
The most popular open source editor
Notepad++7.3.1
Easy-to-use and free code editor
mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),
