如何指定此随机图像脚本

Question

我有这个javascript在点击时显示随机图像：

function pickimg(){
var imagenumber = 4 ;
var randomnumber = Math.random() ;
var rand1 = Math.round( (imagenumber-1) * randomnumber) + 1;
images = new Array
images[1] = "images/1.png"
images[2] = "images/2.png"
images[3] = "images/3.png"
images[4] = "images/4.png"
var image = images[rand1]
document.randimg.src = image

有没有办法确保同一张图片连续两次不显示？

Answer 1

这个小小的算法怎么样？

1. 将最后使用的图像存储在数组的插槽0中
2. 选择索引大于0的随机图像。
3. 显示
4. 将其替换为插槽0中的图像

使用Javascript：

 images = new Array();
 images[0] = "images/1.png" //will be that last used image
 images[1] = "images/2.png"
 images[2] = "images/3.png"
 images[3] = "images/4.png"
 function pickimg(){
     var randomnumber = Math.random();
     // pick a random number from 1 to LENGTH (3)
     var rand1 = Math.round( (images.length-1) * randomnumber)+1;
     var image = images[rand1]; //get the image

    // switch so that the random image will be in the used
    // images slot (slot 0)
    images[rand1] = images[0] 
    images[0] = image 

    document.randimg.src = image
}