var a = ["张三","李四","王五","赵六"]
var a2 = new Array()
function action(str){
var s = document.getElementById("bt").value
if(s=="开始"){
isRun=true
run()
document.getElementById("bt").value="结束"
}else{
isRun=false
document.getElementById("bt").value="开始"
}
}
function run(){
var i = Math.floor(Math.random() * a.length+ 1)-1
document.getElementById("show").innerHTML=a[i]
if(isRun==false){
var b =true
for(var j in a2){
if(a2[j]==i){
b=false
}
}
if(b){
a2[a2.length]=i
return
}
}
setTimeout("run()",10)
}
关键是随机数的实现(伪随机)function myRand(start, end) {
return start + Math.round((Math.random() * (end - start)))
}
这个函数可以得到start到end之间（包括start和end）的随机数，然后根据随机数去点名
<script defer="defer">var arr=new Array("张三","李四","王二","陈一","哈哈")
var n
var num
var timer
function change(){
if(num>=0){
n=GetRnd(0,num)
alert(arr[n])
arr.splice(n,1)
num = arr.length-1
}else{
alert("点完了")
clearInterval(timer)
}
}
function start(){
num = arr.length-1
clearInterval(timer)
timer = setInterval('change()',40)
}
function GetRnd(min,max){
return parseInt(Math.random()*(max-min+1))
}
</script>
<input type="submit" name="button" id="button" value="开始点名" onclick="start()" />
