1. Requirement Description
A company’s year-end lottery needs the following functions
1) The maximum number of attendees can be set according to the actual situation
2) Click " "Start", the big screen scrolls, click "Stop", the winner's number appears on the big screen
3) Display all award winner numbers in the interface
4) No repeated awards
5) The lottery results will not be abnormal due to input errors.
2. Code submission
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 TRANSITIONAL//EN"> <html> <head> <title>某公司周年庆抽奖</title> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <script language="javascript"> var timer; var flag = new Array(100); var existingnum = new Array(100); var clickTimes = 0; var randnum; var cellnum =1; var mobile; var num ; function check_input(){ var input = document.getElementById("real_num").value; var re = /^[1-9]+[0-9]*]*$/; if (!re.test(input)){ alert("请输入正整数"); window.location.href=window.location.href; return false; } } //get the random numbers from the mobile array every 0.05s function setTimer(){ timer = setInterval("getRandNum();",50); document.getElementById("start").disabled = true; document.getElementById("end").disabled = false; } function getRandNum(){ document.getElementById("result").value = mobile[GetRnd(0,num)]; } function GetRnd(min,max){ randnum = parseInt(Math.random()*(max-min+1)); return randnum; } //------------------------------------------------ //turn the input's running down function clearTimer(){ noDupNum(); clearInterval(timer); document.getElementById("start").disabled = false; document.getElementById("end").disabled = true; } // Re defined array:change the length of the array and delete the checked one function noDupNum(){ mobile.removeEleAt(randnum); var o = 0; for(p=0; p<mobile.length;p++){ if(typeof mobile[p]!="undefined"){ mobile[o] = mobile[p]; o++; } } num = mobile.length-1; } function setValues(){ document.getElementById(cellnum).value = document.getElementById("result").value ; cellnum++; } function set_array(){ var real_num = document.getElementById("real_num").value ; mobile= new Array(real_num); var o = 0; for(i=1; i<=real_num;i++){ mobile[o] = i; o++; } num = mobile.length-1; document.getElementById("set_number").disabled = true; } Array.prototype.removeEleAt = function(dx){ if(isNaN(dx)||dx>this.length){return false;} this.splice(dx,1); } </script> </head> <body> <center> <p id="main"> <p> <h1 id="获奖小伙伴">获奖小伙伴</h1> <p> <input id="result" type="text" size="30" style="height:130px;width:800px;border:2px solid red;font-size:120;" readonly/> </p> <p> <input id="start" type="button" value="开始" style="border: 1px solid; border-color: #aaa 000 #000 #aaa; width:4em; background: #fc0;" onclick="setTimer()" /> <input id="end" type="button" value="停" style="border: 1px solid; border-color: #aaa 000 #000 #aaa; width:4em; background: #fc0;"onclick="clearTimer();setValues();" disabled/> </p> <p><strong>一等奖(1名)</strong></p> <table width="190" height="30" border="1"> <tr> <td><input name="text1" type="text" id="3" style="height:30px;width:190px;border:1px solid red;font-size:25;" size="28" readonly/></td> </tr> </table> <p>二等奖(2名)</p> <table width="380" height="30" border="1"> <tr> <td><input name="text2" type="text" id="2" style="height:30px;width:190px;border:1px solid red;font-size:25;" size="28" readonly/></td> <td><input name="text3" type="text" id="1" style="height:30px;width:190px;border:1px solid red;font-size:25;" size="20" readonly/></td> </tr> </table> </p> </p> <p></p> <p></p> <p id="setter" style="border:1px solid;width:45em"> <h3 id="系统设置">系统设置</h3> <table width="300" height="30" border="1"> <tr> <td>活动人数</td> <td><input type="text" id="real_num" style="width:11em"></td> <td><input id="set_number" type="button" value="设置" style="border: 1px solid; border-color: #aaa 000 #000 #aaa; width:4em; background: #fc0;" onclick="check_input();set_array();"/></td> </tr> <tr> </tr> </table> <br/> <input id="set_number" type="button" value="重新开始抽奖" style="border: 1px solid; border-color: #aaa 000 #000 #aaa; width:45em;height: 3em;background: #fc0;" onclick="window.location.href=window.location.href;"/> <p></p> </p> <center> </body> </html>
3. Ugly screenshot
I am ugly, but I am gentle~
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