参考错误未定义

Question

create2.innerHTML =  create2.innerHTML+  " <img onclick = 'a()'  src =' "+ messages[msg].thumb + "'  height='90' width='142'> </a>  ";
    function a (){

    }

So I am trying to include an onlick event on image tag so that when it is click a function is called. However, I am getting the following error :

Uncaught ReferenceError: a is not defined onclick 有人可以解释为什么会这样吗？

Answer 1

这就是为什么使用内联事件不是一个好主意。您的范围是 window，因此它会查找 window 中的点击。当函数在另一个函数中时，您无权访问它。

var img = document.createElement("img");
img.src = messages[msg].thumb;
img.style.height = "90px";
img.style.width = "142px";
img.onclick = a;   //would be better to use addEventListener()
create2.appendChild(img);

参考错误未定义

reference error not defined

javascript

onclick