核心：js的Math对象和Array对象
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<!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>random</title> <style> #awardListDom{width: 100%;} </style></head><body> <label for="awardListDom">奖项列表</label><br> <input type="text" value="" id="awardListDom"> <br> <label for="num">抽到的奖</label><br> <input type="text" value="" id="num"> <br> <button id="submit">开始抽奖</button> <script> /* * 思路：随机抽奖，抽一个奖项便减少一个 * Math 对象方法：http://www.w3school.com.cn/jsref/jsref_obj_math.asp * -random():返回 0 ~ 1 之间的随机数。 * -floor():获取整数 * 数组操作： * - splice(x,y); x:起始位置， y:获取并删除个数 */ function random(min,max){ return Math.floor(min+Math.random()*(max-min)); } var awardListDom=document.getElementById("awardListDom"), num=document.getElementById("num"), submit=document.getElementById("submit"); var awardList=["一等奖","二等奖","二等奖","三等奖","三等奖","三等奖","鼓励奖","鼓励奖","鼓励奖","鼓励奖","谢谢参与","谢谢参与","谢谢参与","谢谢参与","谢谢参与","谢谢参与"]; awardListDom.value=awardList; submit.onclick=function(){ //引用数组 var oldArray=awardList; var rNum=random(0,oldArray.length); if(oldArray.length<1){ awardListDom.value="活动结束"; num.value="活动结束"; } else{ num.value=oldArray[rNum]; oldArray.splice(rNum,1); awardListDom.value=oldArray; } } </script></body></html> |
github:https://github.com/litengdesign/award
