CSS - differences between > and & [duplicate] - css

For example:
div > p.some_class {
/* Some declarations */
}
What exactly does the > sign mean?

> is the child combinator, sometimes mistakenly called the direct descendant combinator.1
That means the selector div > p.some_class only matches paragraphs of .some_class that are nested directly inside a div, and not any paragraphs that are nested further within. This implies that every element matching div > p.some_class necessarily also matches div p.some_class, with the descendant combinator (space), so the two are understandably often confused.
An illustration comparing the child combinator with the descendant combinator:
div > p.some_class {
background: yellow;
}
div p.some_class {
color: red;
}
<div>
<p class="some_class">Some text here</p> <!-- [1] div > p.some_class, div p.some_class -->
<blockquote>
<p class="some_class">More text here</p> <!-- [2] div p.some_class -->
</blockquote>
</div>
Which elements are matched by which selectors?
Matched by both div > p.some_class and div p.some_class
This p.some_class is located directly inside the div, hence a parent-child relationship is established between both elements. Since "child" is a type of "descendant", any child element is by definition also a descendant. Therefore, both rules are applied.
Matched by only div p.some_class
This p.some_class is contained by a blockquote within the div, rather than the div itself. Although this p.some_class is a descendant of the div, it's not a child; it's a grandchild. Therefore, only the rule with the descendant combinator in its selector is applied.
1 Many people go further to call it "direct child" or "immediate child", but that's completely unnecessary (and incredibly annoying to me), because a child element is immediate by definition anyway, so they mean the exact same thing. There's no such thing as an "indirect child".

> (greater-than sign) is a CSS Combinator.
A combinator is something that explains the relationship between the selectors.
A CSS selector can contain more than one simple selector. Between the simple selectors, we can include a combinator.
There are four different combinators in CSS3:
descendant selector (space)
child selector (>)
adjacent sibling selector (+)
general sibling selector (~)
Note: < is not valid in CSS selectors.
For example:
<!DOCTYPE html>
<html>
<head>
<style>
div > p {
background-color: yellow;
}
</style>
</head>
<body>
<div>
<p>Paragraph 1 in the div.</p>
<p>Paragraph 2 in the div.</p>
<span><p>Paragraph 3 in the div.</p></span> <!-- not Child but Descendant -->
</div>
<p>Paragraph 4. Not in a div.</p>
<p>Paragraph 5. Not in a div.</p>
</body>
</html>
Output:
More information about CSS Combinators

As others mention, it's a child selector. Here's the appropriate link.
http://www.w3.org/TR/CSS2/selector.html#child-selectors

It matches p elements with class some_class that are directly under a div.

All p tags with class some_class which are direct children of a div tag.

( child selector) was introduced in css2.
div p{ } select all p elements decedent of div elements, whereas div > p selects only child p elements, not grand child, great grand child on so on.
<style>
div p{ color:red } /* match both p*/
div > p{ color:blue } /* match only first p*/
</style>
<div>
<p>para tag, child and decedent of p.</p>
<ul>
<li>
<p>para inside list. </p>
</li>
</ul>
</div>
For more information on CSS Ce[lectors and their use, check my blog,
css selectors and css3 selectors

html
<div>
<p class="some_class">lohrem text (it will be of red color )</p>
<div>
<p class="some_class">lohrem text (it will NOT be of red color)</p>
</div>
<p class="some_class">lohrem text (it will be of red color )</p>
</div>
css
div > p.some_class{
color:red;
}
All the direct children that are <p> with .some_class would get the style applied to them.

The greater sign ( > ) selector in CSS means that the selector on the right is a direct descendant / child of whatever is on the left.
An example:
article > p { }
Means only style a paragraph that comes after an article.

Related

CSS selector difference: element element vs element>element

What is the difference between the following two CSS selectors?
From the explanation here, they sound the same?
div p{}
Selects all p elements inside div elements
div > p{}
Selects all p elements where the parent is a div element.
The difference is depth. What the w3schools site doesn't explain very well is that E>F only matches immediate children of E, while E F matches descendants of any depth.
Using your example CSS, consider the following HTML snippet:
<div>
<p id="paragraph1">I'm paragraph 1</p>
<ul>
<li><p id="paragraph2">I'm paragraph 2</p></li>
</ul>
</div>
The first ruleset, div p, will match both p blocks. The second one, div > p, will only match paragraph1.
div p{}
This one applies to all p inside div
div>p{}
This one says p needs to be a direct descendent of div
/*This one applies to all childrens (`span`) inside parent*/
div span {
color: red;
}
/*This one says child (`span`) needs to be a direct descendent of parent*/
div > span {
color: green;
}
<div>
<!--(`div`) does not represent an obstacle in both selectors-->
<div>
<span>I live in Duckburg.</span>
</div>
<ul>
<li>
<span>I live in Duckburg.</span>
</li>
</ul>
<span>I live in Duckburg.</span><br>
<span>I live in Duckburg.</span>
</div>

Where I can use + and > in CSS?

This may be a basic question but to me it is still confusing where I can use + or > in CSS.
I see many selectors like li > a or div + span etc. but I am not sure what the difference is and when to use them?
The > sign means select a direct descendant
Example:
CSS
div > ul {
list-style: none;
}
HTML
Here the style would apply to the <ul>
<div>
<ul>
</ul>
</div>
The + sign means select an adjacent sibling
Example:
CSS
p + p
{
font-weight: bold;
}
HTML
Here the style would apply to the latter <p>
<div>
<p></p>
<p></p>
</div>
The selectors are extensively explained in the W3 CSS spec, but here is a digest:
Immediate child selector
The > selector is the immediate child selector. In your example li > a, the rule would select any <a> element that is an immediate child of an <li> element.
The rule would select the anchor in this example:
<ul>
<li>An anchor</li>
</ul>
The adjacent sibling selector
The + selector is the adjacent sibling selector. In your example div + span, the rule would select any <span> elements that is immediately preceded by a <div> element, and where they both share the same parent.
The span element would be selected in this case:
<article>
<div>A preceding div element</div>
<span>This span would be selected</span>
</article>
The > is the direct child selector. In your example of li > a, this will only select <a> tags that are direct descendants of the <li>.
The + means siblings of the selected elements. In your example, div + span would select any <span>s next to a <div> (with the same parent).
li > a would only select a elements that are direct descendants of li elements. div + span would only select span elements that follow a div element.
Read more in #bažmegakapa's link: http://www.w3.org/TR/CSS2/selector.html#pattern-matching
I'm not sure about the + sign but the > sign in css means direct child of, consider this
div > h1 { color: red; }
This will style all h1 tags that are a direct child of a div.
<h1>BLAH</h1>
<div>
<h1>BLAH</h1>
</div>
In that case the first h1 would be left alone, the second because it is a direct child of the div tag would be red.

CSS First-child bug? or intended behavior?

I have the following set up
.test div:first-child {};
<div class="test" id="one">
<div id="two">
<div id="three">
</div>
</div>
</div>
Somehow div#three inherits the first-child styles, even though it is not the first-child of div.test. Is this intentional by the browsers? Can someone explain this?
While #two is the first child of #one but #three isn't, #three is still the first child of #two. So both inner divs get the styles.
The descendant combinator (the space character) in your selector tells the browser to select any div in any level of nesting from .test, as long as it's contained somewhere within an element with that class. The :first-child pseudo-class says to only select an element if it's the first child of its parent, whatever that parent may be, not just the element represented on the left side of the combinator.
If you only want to target the first child of .test, use the child combinator >:
.test > div:first-child {}
Because > expresses a parent-child relationship, it is safe to imply that the parent concerned by div:first-child is represented by .test.
This is the intended behaviour. You need to write your CSS rule like this:
.test > div:first-child
The > ensures only the first child of the .test element is selected. Without it, any div that is the first child of any node within .test is selected.

What does the "+" (plus sign) CSS selector mean?

This question's answers are a community effort. Edit existing answers to improve this post. It is not currently accepting new answers or interactions.
For example:
p + p {
/* Some declarations */
}
I don't know what the + means. What's the difference between this and just defining a style for p without + p?
See adjacent selectors on W3.org.
In this case, the selector means that the style applies only to paragraphs directly following another paragraph.
A plain p selector would apply the style to every paragraph in the page.
This will only work on IE7 or above. In IE6, the style will not be applied to any elements. This also goes for the > combinator, by the way.
See also Microsoft's overview for CSS compatibility in Internet Explorer.
It's the Adjacent sibling selector.
From Splash of Style blog.
To define a CSS adjacent selector, the
plus sign is used.
h1+p {color:blue;}
The above CSS code will format the
first paragraph after (not inside) any h1 headings
as blue.
h1>p selects any p element that is a direct (first generation) child (inside) of an h1 element.
h1>p matches <h1> <p></p> </h1> (<p> inside <h1>)
h1+p will select the first p element that is a sibling (at the same level of the dom) as an h1 element.
h1+p matches <h1></h1> <p><p/> (<p> next to/after <h1>)
The + sign means select an "adjacent sibling"
For example, this style will apply from the second <p>:
p + p {
font-weight: bold;
}
<div>
<p>Paragraph 1</p>
<p>Paragraph 2</p>
</div>
Example
See this JSFiddle and you will understand it: http://jsfiddle.net/7c05m7tv/
(Another JSFiddle: http://jsfiddle.net/7c05m7tv/70/)
Browser Support
Adjacent sibling selectors are supported in all modern browsers.
Learn more
http://css-tricks.com/almanac/selectors/a/adjacent-sibling/
http://www.w3.org/TR/CSS2/selector.html#adjacent-selectors
https://developer.mozilla.org/en-US/docs/Web/CSS/Adjacent_sibling_selectors
"+" is the adjacent sibling selector. It will select any p DIRECTLY AFTER a p (not a child or parent though, a sibling).
The + combinator is called the Adjacent sibling combinator / Next-sibling combinator.
For example, the combination of p + p selectors, selects the p elements immediately following the p elements
It can be thought of as a "looking alongside" combination that checks for the immediately following element.
Here is a sample snippet to make things more clear:
body {
font-family: Tahoma;
font-size: 12px;
}
p + p {
margin-left: 10px;
}
<div>
<p>Header paragraph</p>
<p>This is a paragraph</p>
<p>This is another paragraph</p>
<p>This is yet another paragraph</p>
<hr>
<p>Footer paragraph</p>
</div>
Since we are on the same topic, it is worth mentioning another combinator, ~, which is the General sibling combinator / Subsequent-sibling combinator
For example, p ~ p selects all the p which follows the p doesn't matter where it is, but both p should be having the same parent.
Here is what it looks like with the same markup:
body {
font-family: Tahoma;
font-size: 12px;
}
p ~ p {
margin-left: 10px;
}
<div>
<p>Header paragraph</p>
<p>This is a paragraph</p>
<p>This is another paragraph</p>
<p>This is yet another paragraph</p>
<hr>
<p>Footer paragraph</p>
</div>
Notice that the last p is also matched in this sample.
The + selector targets the one element after. On a similar note, the ~ selector targets all the elements after. Here's a diagram, if you're confused:
+ presents one of the relative selectors. Here is a list of all relative selectors:
div p - All <p> elements inside of a <div> element are selected.
div > p - All <p> elements whose direct parent is <div> are selected. It works backwards too (p < div)
div + p - All <p> elements placed immediately after a <div> element are selected.
div ~ p - All <p> elements that are preceded by a <div> element are selected.
Here is some more about selectors.
It would match any element p that's immediately adjacent to an element 'p'. See: http://www.w3.org/TR/CSS2/selector.html
p+p{
//styling the code
}
p+p{
} simply mean find all the adjacent/sibling paragraphs with respect to first paragraph in DOM body.
<div>
<input type="text" placeholder="something">
<p>This is first paragraph</p>
<button>Button </button>
<p> This is second paragraph</p>
<p>This is third paragraph</p>
</div>
Styling part
<style type="text/css">
p+p{
color: red;
font-weight: bolder;
}
</style>
It will style all sibling paragraph with red color.
final output look like this

CSS Child vs Descendant selectors

I am a bit confused between these 2 selectors.
Does the descendent selector:
div p
select all p within a div whether or not it's an immediate descedent? So if the p is inside another div it will still be selected?
Then the child selector:
div > p
Whats the difference? Does a child mean immediate child? Eg.
<div><p>
vs
<div><div><p>
will both be selected, or not?
Just think of what the words "child" and "descendant" mean in English:
My daughter is both my child and my descendant
My granddaughter is not my child, but she is my descendant.
Yes, you are correct. div p will match the following example, but div > p will not.
<div><table><tr><td><p> <!...
The first one is called descendant selector and the second one is called child selector.
Bascailly, "a b" selects all b's inside a, while "a>b" selects b's what are only children to the a, it will not select b what is child of b what is child of a.
This example illustrates the difference:
div span{background:red}
div>span{background:green}
<div><span>abc</span><span>def<span>ghi</span></span></div>
Background color of abc and def will be green, but ghi will have red background color.
IMPORTANT: If you change order of the rules to:
div>span{background:green}
div span{background:red}
All letters will have red background, because descendant selector selects child's too.
In theory:
Child => an immediate descendant of an ancestor (e.g. Joe and his father)
Descendant => any element that is descended from a particular ancestor (e.g. Joe and his great-great-grand-father)
In practice: try this HTML:
<div class="one">
<span>Span 1.
<span>Span 2.</span>
</span>
</div>
<div class="two">
<span>Span 1.
<span>Span 2.</span>
</span>
</div>
with this CSS:
span { color: red; }
div.one span { color: blue; }
div.two > span { color: green; }
http://jsfiddle.net/X343c/1/
Be aware that the child selector is not supported in Internet Explorer 6.
(If you use the selector in a jQuery/Prototype/YUI etc selector rather than in a style sheet it still works though)
div p
Selects all 'p' elements where at least one parent, grandparent etc. is a 'div' element
div > p
It means immediate children
Selects all 'p' elements where the parent is a 'div' element
div > p matches ps that have a div parent - <div><p> in your question
div p matches ps that have a div ancestor (parent, grandparent, great grandparent, etc.) - <div><p> and <div><div><p> in your question
CSS selection and applying style to a particular element can be done through traversing through the dom element
[Example
Example
.a .b .c .d{
background: #bdbdbd;
}
div>div>div>div:last-child{
background: red;
}
<div class='a'>The first paragraph.
<div class='b'>The second paragraph.
<div class='c'>The third paragraph.
<div class='d'>The fourth paragraph.</div>
<div class='e'>The fourth paragraph.</div>
</div>
</div>
</div>

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