JavaScript圖像源更改addEventListener“單擊”事件

Question

嘗試使用JavaScript將圖片來源從images / small /更改為images / medium /

我已經嘗試了以下代碼，但是由於某些原因，沒有選擇click事件，感謝對此的任何幫助。

使用Javascript

var thumbs = document.getElementById("thumbnails");

thumbs.addEventListener("click", function (i) {


    if (i.target.nodeName.toLowerCase() == "img") {
        // get image filename of clicked thumbnail
        var clickedImageSource = i.target.src;

        // replace the folder name of the image 
        var newSrc = clickedImageSource.replace("small","medium");


    }

});

HTML

<div id="thumbnails">
        <img src="images/small/Home.jpg" title="Home" />
        <img src="images/small/Office.jpg" title="Office" />
        <img src="images/small/Park.jpg" title="Park" />
        <img src="images/small/Hills.jpg" title="Hills" />
        <img src="images/small/HaveEyes.jpg" title="HaveEyes" />
    </div>

Answer 1

您不能在DOM元素可用之前附加事件偵聽器。

 <script> // executed before dom is ready. var thumbs = document.getElementById("thumbnails"); thumbs.addEventListener("click", function(i) { console.log('clicked'); }); </script> <div id="thumbnails"> <img src="images/small/Home.jpg" title="Home" /> <img src="images/small/Office.jpg" title="Office" /> <img src="images/small/Park.jpg" title="Park" /> <img src="images/small/Hills.jpg" title="Hills" /> <img src="images/small/HaveEyes.jpg" title="HaveEyes" /> </div> <script> // executed after dom is ready. var thumbs = document.getElementById("thumbnails"); thumbs.addEventListener("click", function(i) { console.log('clicked'); }); </script>