programming-examples/js/Htmldom/Display a random image by clicking on a button.js

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JavaScript
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2019-11-15 12:59:38 +01:00
function display_random_image()
{
var theImages = [{
src: "http://farm4.staticflickr.com/3691/11268502654_f28f05966c_m.jpg",
width: "240",
height: "160"
}, {
src: "http://farm1.staticflickr.com/33/45336904_1aef569b30_n.jpg",
width: "320",
height: "195"
}, {
src: "http://farm6.staticflickr.com/5211/5384592886_80a512e2c9.jpg",
width: "500",
height: "343"
}];
var preBuffer = [];
for (var i = 0, j = theImages.length; i < j; i++) {
preBuffer[i] = new Image();
preBuffer[i].src = theImages[i].src;
preBuffer[i].width = theImages[i].width;
preBuffer[i].height = theImages[i].height;
}
// create random image number
function getRandomInt(min,max)
{
// return Math.floor(Math.random() * (max - min + 1)) + min;
imn = Math.floor(Math.random() * (max - min + 1)) + min;
return preBuffer[imn];
}
// 0 is first image, preBuffer.length - 1) is last image
var newImage = getRandomInt(0, preBuffer.length - 1);
// remove the previous images
var images = document.getElementsByTagName('img');
var l = images.length;
for (var p = 0; p < l; p++) {
images[0].parentNode.removeChild(images[0]);
}
// display the image
document.body.appendChild(newImage);
}