javascript 未捕获的类型错误：无法在 Google Chrome 中设置未定义的属性“值”
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Uncaught TypeError: Cannot set property 'value' of undefined in Google Chrome
提问by Opec
In my page A, there is a textarea defined like this:
在我的页面 A 中，有一个 textarea 定义如下：
<textarea readonly wrap="Physical" cols="50" rows="2" name="Attr">
The page A opens page B in a popup (by window.open('PageB')).
页面 A 在弹出窗口中打开页面 B (by window.open('PageB'))。
In the page B, the button "Save" executes this line of code:
在页面B中，按钮“保存”执行这行代码：
window.parent.opener.document.all.Attr.value='Value 1, Value 2,';
This one causes an error in Google Chrome (error: "Uncaught TypeError: Cannot set property 'value' of undefined") but works perfectly with Internet Explorer and Mozilla Firefox. I have read that document.allis old and should be replaced by document.getElementByIdwhich I did but with no success (error: "Uncaught TypeError: Cannot set property 'value' of null").
这会导致 Google Chrome 出现错误（错误：“Uncaught TypeError: Cannot set property 'value' of undefined”）但与 Internet Explorer 和 Mozilla Firefox 完美配合。我读过它document.all是旧的，应该替换为document.getElementById我所做的但没有成功（错误：“未捕获的类型错误：无法设置空值的属性”）。
If I replace document.allby document.forms[0], it works in all browsers including Google Chrome. But that doesn't seem to be a good solution as the page B could be called by other pages than Page A and that could have more than one form.
如果我替换document.all为document.forms[0]，则它适用于包括 Google Chrome 在内的所有浏览器。但这似乎不是一个好的解决方案，因为页面 B 可以被页面 A 之外的其他页面调用，并且可能有多个表单。
Could anyone tell me what I am doing wrong?
谁能告诉我我做错了什么？
Thanks in advance!
提前致谢！
Opec.
欧佩克。
回答by scrblnrd3
Why can't you just assign it an id an access it through that?
为什么你不能给它分配一个 id 并通过它访问它？
<textarea id="text" readonly wrap="Physical" cols="50" rows="2" name="Attr">
and in your javascript
并在您的 javascript 中
document.getElementById("text").value="Value 1, value 2"
Here is a JSFiddle demonstrating it
这是一个展示它的 JSFiddle
