javaScript產生隨機數的用法小結

var chars = ['0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'];
function generateMixed(n) {
 var res = "";
 for(var i = 0; i < n ; i ++) {
 var id = Math.ceil(Math.random()*35);
 res += chars[id];
 }
 return res;
}

random函數返回值 
返回0和1之間的偽隨機數，可能為0，但總是小于1，[0,1) 
random函數示例 
//返回隨機數 
document.write(Math.random()); 
//返回10-20的隨機數 
document.write(Math.random()*(20-10)+10); 
//返回指定范圍的隨機數(m-n之間)的公式 
document.write(Math.random()*(n-m)+m); 

var now=new Date(); 
var number = now.getSeconds(); //這將產生一個基于目前時間的0到59的整數。 
var now=new Date(); 
var number = now.getSeconds()%43; //這將產生一個基于目前時間的0到42的整數。 

<script type="text/javascript"> 
function MathRand() 
{ 
var Num=""; 
for(var i=0;i<6;i++) 
{ 
Num+=Math.floor(Math.random()*10); 
} 
document.getElementById("Lb_Random").innerText=Num; 
document.getElementById("Lb_Random").innerHTML=Num; 
} 
</script>

<script language="javascript"> 
function randomString(len) {
　　len = len || 32;
　　var $chars = 'ABCDEFGHJKMNPQRSTWXYZabcdefhijkmnprstwxyz2345678'; /****默認去掉了容易混淆的字符oOLl,9gq,Vv,Uu,I1****/
　　var maxPos = $chars.length;
　　var pwd = '';
　　for (i = 0; i < len; i++) {
　　　　pwd += $chars.charAt(Math.floor(Math.random() * maxPos));
　　}
　　return pwd;
}
document.write(randomString(32));
</script> 

<script> 
function GetRandomNum(Min,Max)
{ 
var Range = Max - Min; 
var Rand = Math.random(); 
return(Min + Math.round(Rand * Range)); 
} 
var num = GetRandomNum(1,10); 
alert(num); 
</script> 
var chars = ['0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'];
function generateMixed(n) {
 var res = "";
 for(var i = 0; i < n ; i ++) {
 var id = Math.ceil(Math.random()*35);
 res += chars[id];
 }
 return res;
}

timestamp = timestamp/1000;
<script type="text/javascript">
function randomChar(l) {
var x="0123456789qwertyuioplkjhgfdsazxcvbnm";
var tmp="";
var timestamp = new Date().getTime();
for(var i=0;i< l;i++) {
tmp += x.charAt(Math.ceil(Math.random()*100000000)%x.length);
}
return timestamp+tmp;