jQuery 在jQuery中，$('body')可以选择body元素，而$('body')可以和$('some text')一样，那么如何区分呢？
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In jQuery, $('body') can be selecting the body element, but $('body') can be just like $('some text'), so how to distinguish?
提问by nonopolarity
The reason is that we can do
原因是我们可以做到
$('<div>some text</div>').prependTo('#someDiv')
so, this is also ok to do:
所以，这也可以：
$('some text').prependTo('#someDiv')
but we can't change some textto body? bodyis just as good as any text...
但我们不能更改some text为body? body和任何文字一样好......
(the above code is adding some textto the div with id someDiv, so what if I want to add the word bodyto the div?)
（上面的代码是将some textid添加到 div 中someDiv，那么如果我想将单词添加body到 div 中呢？）
but $('body') becomes a selector for the body element... so is there a rule that says, we can use any text as HTML code, so long as it is not the name of HTML elements?
但是 $('body') 变成了 body 元素的选择器......所以有没有规则说，我们可以使用任何文本作为 HTML 代码，只要它不是 HTML 元素的名称？
采纳答案by Nick Craver
Basically this is never valid:
基本上这永远不会有效：
$('generic text here, *not* a selector or HTML');
That should alwaysbe either a selector (finding an element) or html (creating element(s)), you can view the API for $()here.
这应该始终是选择器（查找元素）或 html（创建元素），您可以在$()此处查看 API。
You want to use one of the other DOM Insertion methodshere, .prepend()in this case:
您想在这里使用其他DOM 插入方法之一，.prepend()在这种情况下：
$('#someDiv').prepend('any text or html here is valid, <b>Hey look bold</b>.');
回答by Sean Hogan
If it contains html tags then it is treated as html (except it strips text before the first tag and after the last). eg $("<div>some text</div>"). Otherwise it is treated as a selector, eg $("some text").
如果它包含 html 标签，则将其视为 html（除了它在第一个标签之前和最后一个标签之后去除文本）。例如$("<div>some text</div>")。否则，它将被视为选择器，例如$("some text").
回答by RoToRa
Dealing with text nodes isn't JQuery's strong suit. You could use normal DOM methods:
处理文本节点并不是 JQuery 的强项。您可以使用普通的 DOM 方法：
$('#someDiv')[0].appendChild(document.createTextNode("body"));
回答by Mario Menger
This is because jQuery considers selectors before creating HTML snippets. "body" is a valid selector and will be used as a selector.
这是因为 jQuery 在创建 HTML 片段之前会考虑选择器。“body”是一个有效的选择器，将用作选择器。
You'd be better of using the prepend function to prepend HTML or text to a node:
您最好使用 prepend 函数将 HTML 或文本添加到节点：
$('#someDiv').prepend('some text');
The value passed to prepend is not used a selector and you could add the text "body".
传递给 prepend 的值不用作选择器，您可以添加文本“body”。
