是否有一种方法可以继承CSS简写的一个元素 [英] Is there a way to inherit only one element of CSS shorthand
问题描述
来自css新手的一个快速问题。我试图减少我的CSS文件的大小，通过使用简写的某些属性，如padding / marginins等。在某些情况下，我想要，例如，指定margin-top，margin-left和margin-bottom，但继承margin-right。我尝试了
A quick question from a css newbie here. I'm trying to reduce the size of my CSS files by using shorthand for certain properties such as padding/margins/etc. In certain cases I want to, for example, specify margin-top, margin-left, and margin-bottom, but inherit margin-right. I tried
margin: 10px inherit 11px 12px;
但不起作用，因为CSS inherit关键字继承所有或什么都不。
but that doesn't work because the CSS inherit keyword inherits all or nothing.
是否有一种方法可以将该标记标记为跳过，并执行
Is there a way to mark that one as skipped and do something like
margin: 10px 11px 12px;
margin-right: inherit;
并且CSS知道我跳过一个4值速记中的一个值，作为一个3价值的速记？
and have CSS know that I am skipping one value in a 4-value shorthand, and not interpret it as a 3-value shorthand?
有没有人知道一个简单的方法来让这个工作？或者我应该只使用长手在我不指定所有四个值的情况下？
谢谢！
Does anyone know an easy way to get this to work? Or should I just use long-hand in cases where I don't specify all four values? Thanks!
推荐答案
如果覆盖该值，最后一个声明将被忽略， ：
If you overwrite the value, the last declaration will be ignored, so you can just do this:
element {
margin: 10px 0 11px 12px;
margin-right: inherit;
}
...其中0可以是任何值 * <
...where "0" here can be any value * see below.
这不会按预期工作：
margin: 10px 11px 12px;
这实际上会产生这些值：
That would actually produce these values:
margin-top: 10px;
margin-right: 11px;
margin-bottom: 12px;
margin-left: 11px; /* copied from margin-right's value since it's missing */
c $ c> inherit 采用应用于父元素的任何值，并且不会像通常所想的那样将其重置为默认。因此，如果它是 margin-right：100px 的直接子对象，它将继承该值。
Just in case, note that inherit takes whatever value is applied to the parent element, and does not "reset" it to a "default" as is commonly thought. So, if it's an immediate child of something with margin-right:100px, it will inherit that value. It's a rare case you actually want to inherit a property like margin, you may be thinking it does something that it really doesn't.
EDIT 这是一个罕见的情况，你实际上想要继承一个属性，如边际，你可能认为它做的事情， >：正如我在评论中所说，我不知道不能使用继承的速记（至少，为边缘），直到你带来这个问题向上。我在这里得到一些奇怪的结果，我真的不知道该怎么做： http://jsfiddle.net/ fpHb9 / 1 /
EDIT: As I said in the comment, I wasn't aware of not being able to use inherit in shorthand (at the very least, for margin) until you brought this question up. I'm getting some rather strange results here, and I honestly don't know what to make of it: http://jsfiddle.net/fpHb9/1/
因此，除非有其他人能够参与并更好地了解此行为，请小心处理。最好只是明确设置边距。
So, until someone else can come along and provide a better understanding of this behavior, be careful with this. It might be better to just explicitly set the margin.
EDIT2 ：我想我解决了演示中的谜题。我没有引用的方便，但似乎因为 inherit 是无效的简写，使用它将使整个声明无效。所以像这样的东西将无法正常工作：
EDIT2: I think I solved the mystery in the demo. I don't have reference handy, but it seems that since inherit is invalid in shorthand, using it will invalidate the entire declaration. So something like this will not work as expected:
margin:20px inherit 20px 20px; /* this line gets ignored completely */
margin-right:inherit;
因此，修改我之前的声明：
So, to amend my previous statement:
...其中，0可以是此处记录的任何有效margin width值：
http://www.w3.org/TR/CSS2/box.html#margin-properties 。
...where "0" here can be any valid margin width value as documented here:
http://www.w3.org/TR/CSS2/box.html#margin-properties.
原谅我长久以来的回答，你引起我的好奇，如何工作（或不工作）。
Forgive me for the long winded answer, you aroused my curiosity as to how this works (or doesn't work).
这篇关于是否有一种方法可以继承CSS简写的一个元素的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
