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如何根据选择选项框中的选择显示数组值?

[英]How to display an array value based on a selection from a select option box?

<!DOCTYPE html>
<html>
<body bgcolor="#999966">
 <select id="myFruitSelect">
    <option value="0"> Please Choose a Fruit </option>
    <option value="1"> Apple</option>
    <option value="2">Orange</option>
    <option value="3">Pineapple</option>
    <option value="4">Banana</option>
    <option value="5"> Watermelon </option>
  </select>
</form>
<br>
<button onclick="myFunction()"> Select Your Fruit</button>
<img id="outputImage" src=""/>

<script>
function myFunction() {
    var n =parseInt(x) -1;
    var pictures=[ "apple.png", "orange.png", "pineapple.png", "banana.png", "Watermelon.png"];
    var x = document.getElementById("myFruitSelect").value; 
    document.getElementById('outpu​tImage').src = pictures[n-1];
}
</script>
</body>
</html>

任何帮助或正确方向的点是值得赞赏的

我正在尝试创建一个用户从下拉列表中选择一个选项的页面,然后根据用户的选择显示一个数组值。 我无法弄清楚如何根据用户选择访问数组值。 我只能使用HTML和脚本,所以没有jQuery的答案。

这行似乎有问题( var n =parseInt(x) -1; ),因为在定义它之前使用x 您可以将该声明移到var x声明下面,或者完全删除它:

 <!DOCTYPE html> <html> <body bgcolor="#999966"> <select id="myFruitSelect"> <option value="0"> Please Choose a Fruit </option> <option value="1"> Apple</option> <option value="2">Orange</option> <option value="3">Pineapple</option> <option value="4">Banana</option> <option value="5"> Watermelon </option> </select> </form> <br> <button onclick="myFunction()"> Select Your Fruit</button> <img id="outputImage" src=""/> <script> function myFunction() { var pictures= [ "apple.png", "orange.png", "pineapple.png", "banana.png", "Watermelon.png"]; var x = document.getElementById("myFruitSelect").value; document.getElementById('outputImage').src = pictures[parseInt(x, 10)-1]; } </script> </body> </html> 

这很少见,显然你的代码还可以,但是你给你的图像元素的id和你document.getElementById的id有区别.getElementById对我来说似乎都是一样的但是当我从图像中复制并粘贴id时document.getElementById()它完美无缺。

<!DOCTYPE html>
<html>
<body bgcolor="#999966">
<form>
 <select id="myFruitSelect">
    <option value="0"> Please Choose a Fruit </option>
    <option value="1"> Apple</option>
    <option value="2">Orange</option>
    <option value="3">Pineapple</option>
    <option value="4">Banana</option>
    <option value="5"> Watermelon </option>
  </select>
</form>

<br>

<button onclick="myFunction()"> Select Your Fruit</button>

<img id="outputImage" src=""/>



<script>
function myFunction() {

    var pictures=[ "apple.png", "orange.png", "pineapple.png", "banana.png", "Watermelon.png"];
     x = document.getElementById("myFruitSelect").value;
     //This will give you index of the selected option.
     //As the array starts from 0 , we need to subtract 1 to access the particular picture
     y = parseInt(x);
     m = y-1;
     console.log(pictures[m]);
    document.getElementById('outpu​tImage').setAttribute("src", pictures[m]);

    }
</script>

</body>
</html>

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