未捕获的类型错误无法读取未定义的 Javascript 的属性“0”
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uncaught typeerror cannot read property '0' of undefined Javascript
提问by arabello
here is part of my function code that makes an error on javascript error console ( Google Chrome)
这是我的函数代码的一部分，它在 javascript 错误控制台（谷歌浏览器）上出错
function premuto(x){
if(x.Clickable){
x.Selected = !x.Selected;
if (x.Selected){
x.style.backgroundColor ='lightblue';
y = document.getElementById('spazio');
y.innerHTML = y.innerHTML + x.innerHTML;
sequenza[indice] = x.Number;
indice++;
}
error compares at line "sequenza[indice] = x.Number;"
错误比较在“sequenza[indice] = x.Number;”行
What's wrong?
怎么了？
Thanks
谢谢
回答by Kemal Da?
Your indiceis 0 and sequenzais undefined. In javascript it always raises a type error, if you try to reach undefined variable's properties or methods. You should debug your code and see exactly when sequanza becomes undefined.
你indice是 0sequenza是undefined。在 javascript 中，如果您尝试访问未定义变量的属性或方法，它总是会引发类型错误。您应该调试您的代码，并准确查看 sequanza 何时变为undefined.
