如何使用Javascript（关闭）取消选中复选框？

Question

I have following code in my javascript code

goog.dom.$(changeIdStr).getElementsByTagName('input')[0].checked = false console.log(typeof(goog.dom.$(changeIdStr).getElementsByTagName('input')[0].checked) console.log(goog.dom.$(changeIdStr).getElementsByTagName('input')[0].checked); console.log(goog.dom.$(changeIdStr).innerHTML);

and the corresponding log is

boolean

false

<label><input type="checkbox"
onclick="handleSelectedUrl('selected_1_0', 'selected_', 'url_')"
name="selected[]" value="http://www.imdb.com/title/tt2948356/"
checked=""><a href="http://www.imdb.com/title/tt2948356/"
target="_blank">http://www.imdb.com/title/tt2948356/</a></label>

So why the checked attribute is false, there is still checked="" in the HTML.

Answer 1

需要checked="true"而不是checked=""以返回真。

Answer 2

For a checkbox, by default if it is false then there is no checked attribute added in the html.

But after that if you make it true or checked then attribute gets added and set to "checked". If you make it unchecked or false, it becomes empty but the checkbox attribute doesn't get removed. This is equivalent to checkbox false.