javascript javascript按钮从数组中选择随机项目
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javascript button to pick random item from array
提问by user2419017
Please can someone help. I am trying to create a basic button in javascript that when clicked picks a value at random from my array and display it on the screen, each time the button is clicked it should pick a new item from the array. I know how to write the array
请有人帮忙。我正在尝试在 javascript 中创建一个基本按钮，当单击它时，它会从我的数组中随机选取一个值并将其显示在屏幕上，每次单击该按钮时，它都应该从数组中选取一个新项目。我知道如何写数组
var myarray = new Array("item1", "item2", "item3");
I just dont know how to do the button part. Any help would be great. I know it may be easier to do this in jQuery, but I really want to get my head round javascript before I tackle jQuery (please be gentle I am new to this lol)
我只是不知道如何做按钮部分。任何帮助都会很棒。我知道在 jQuery 中执行此操作可能更容易，但我真的很想在处理 jQuery 之前先了解一下 javascript（请保持温和，我是这个哈哈的新手）
回答by Sachin
You can call a function on button click to print the value like this
您可以在按钮单击时调用函数以打印这样的值
<input type="button" id="btnSearch" value="Search" onclick="GetValue();" />
<p id="message" ></p>
JS
JS
function GetValue()
{
var myarray= new Array("item1","item2","item3");
var random = myarray[Math.floor(Math.random() * myarray.length)];
//alert(random);
document.getElementById("message").innerHTML=random;
}
回答by Guanxi
Use Random function of javascript to generate a random number between upper and lower limit of your array. Then use
使用 javascript 的 Random 函数在数组的上限和下限之间生成一个随机数。然后使用
myarray[Math.round(Math.random() * (myarray.length - 1))]
to access a random value from the array.
访问数组中的随机值。
You can use thislink to see hot to generate a random number between a min and max number. (for your case min will always be 0).
您可以使用此链接查看 hot 以生成最小和最大数字之间的随机数。（对于您的情况 min 将始终为 0）。
回答by Epsil0neR
Try this one: HTML:
试试这个：HTML：
<input type="button" click="randomize()" value="Click me" />
JS:
JS：
function randomize(){
var myarray = new Array("item1", "item2", "item3");
var randomId = Math.floor((Math.random()*myarray.length));
var randomItem = myarray[randomid];
alert(randomItem);
}
回答by aquinas
JS:
JS：
var arr = ["foo","bar","baz"];
function getItem(){
document.getElementById("something").innerHTML = arr[Math.floor(Math.random() * arr.length)];
}
HTML
HTML
<div id="something"></div>
<input type="button" onclick="getItem()" value="Click me"/>
回答by Gabriel Petrovay
Here is an example:
下面是一个例子：
The steps are:
步骤是：
Create a button element and give it an ID:
<button id="button1">Show random item</button>Get a reference to the button in your script:
document.getElementById("button1");Compute a random index in your array based on the array length:
Math.floor(Math.random() * array.length)Add a
clickevent handler to your button that calls the random computation at step 3 and shows it a way you want:button.onclick = function() { … }
创建一个按钮元素并给它一个 ID：
<button id="button1">Show random item</button>获取对脚本中按钮的引用：
document.getElementById("button1");根据数组长度计算数组中的随机索引：
Math.floor(Math.random() * array.length)click向您的按钮添加一个事件处理程序，该处理程序在步骤 3 中调用随机计算并以您想要的方式显示它：button.onclick = function() { … }
All in one:
一体：
var button = document.getElementById("button1");
var myarray = ["a", "b", "c", "d"];
button.onclick = function() {
alert(myarray[Math.floor(Math.random() * myarray.length)]);
};
