jQuery 如何检查孩子是否存在
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How to check if child exists
提问by Scarface
I have a div which could potentially have a hyperlink with an id of reply. How can I check if that a[id=reply]exists? I thought it might be something like this but it alerts the message even if that hyperlink does not exist.
我有一个 div，它可能有一个带有回复 id 的超链接。我如何检查它是否a[id=reply]存在？我认为它可能是这样的，但即使该超链接不存在，它也会提醒消息。
if($('div[chunk_id='+reply_chunk_id+']').children('a[id=reply]')){
alert('test');
}
回答by Nick Craver
Check the .lengthof the selector to see how many elements it matched, in this case:
检查.length选择器的 以查看它匹配的元素数量，在这种情况下：
if($("#reply").length) {
//child exists
}
However, it soundslike you have multiple elements with id="reply", which is invalid. Instead use class="reply"and your selector will look like this:
但是，听起来您有多个带有 的元素id="reply"，这是无效的。而是使用class="reply"，您的选择器将如下所示：
if($("div[chunk_id='"+reply_chunk_id+"'] > a.reply").length){
//child exists
}
回答by darksioul
Another way to do it :
另一种方法：
if($("div[chunk_id="+reply_chunk_id+"]").children('.reply').length > 0){
// it exists
}
