How to make a box with arrow in CSS?

问题

Making round corner is easy. but any idea to make the arrow on left side without using image.

Is it possible to make possible with

only one elements <p>....</p>

body {
  background: #ff004e;
  padding: 40px
}
p {
  background: white;
  -webkit-border-radius: 10px;
  -moz-border-radius: 10px;
  border-radius: 10px;
  width: 250px;
  height: 150px
}

<p></p>

回答1:

Like this :

.arrow {
    border: solid 10px transparent;
    border-right-color: #FFF;
}

Demo : http://jsfiddle.net/sparkup/edjdxjf2/

UPDATE :

It can also be achieved without empty elements with the css property :before

element:before {
    content: "";
    position: absolute;
    top: 50%;                         // half way down (vertical center).
    margin-top: -15px;                // adjust position, arrow has a height of 30px. 
    left:-30px;
    border: solid 15px transparent;
    border-right-color: #FFF;
    z-index: 1;
}

Demo : http://jsfiddle.net/sparkup/y89f1te0/

hope it helps

回答2:

Chris Coyier has an excellent roundup of the possible shapes built in CSS using a single element (and before/afters): http://css-tricks.com/examples/ShapesOfCSS/

回答3:

Standard Tool-tip

If you want a simple arrow, then you can add a pseudo element with border-right.

body {
    background:#ff004e;
    padding:40px;
}
p {
    background:white;
    border-radius: 10px;
    width:250px;
    height:150px;
    position: relative;
    display: inline-block;
}
p:before {
    content:"";
    position: absolute;
    height: 0px;
    width: 0px;
    top: 60px;
    left: -29px; /* 1px buffer for zooming problems while rendering*/
    border-width: 15px;
    border-color: transparent white transparent transparent;
    border-style: solid;
}

<p></p>

FIDDLE 1

Flat edge Tool-tip

If you want a flat edge for arrow, try this :

body {
    background: #ff004e;
    padding:40px;
}
p {
    background:white;
    border-radius: 10px;
    width:250px;
    height:150px;
    position: relative;
    display: inline-block;
}
p:before {
    content:"";
    position: absolute;
    height: 45px;
    width: 16px; /* 1px buffer for zooming problems while rendering*/
    top: 50px;
    left: -15px; 
    background: white;
}
p:after {
    content:"";
    position: absolute;
    height: 40px;
    width: 15px;
    border-radius: 0 40px 40px 0;
    top: 75px;
    left: -15px;
    background: #ff004e;
    box-shadow: 0 -45px 0 0 #ff004e;
}

<p></p>

FIDDLE 2

回答4:

My answer (with no flat edge), added some calculation formula:

.mainBox {
    border: solid 1px #e0e0e0;        
}

.mainBox:before {
    content:"";
    position: absolute;
    /*The right value must be calculated with: (top value of after) - (top value of before) = (right value of before) */
    /*example: (-4px) - (-7px) = 3px*/
    right: 72px; 
    /*The `top` value must be identical to border-width*/
    top: -7px; 
    width: 0;
    height: 0;
    border-style: solid;
    /*The `border-width` value must be identical to top*/
    border-width: 0 7px 7px 7px;
    /*The border color 3rd (#e0e0e0) value must be identical to its parent border color*/
    border-color: transparent transparent #e0e0e0 transparent;
    /*The (z-index of before) must at least one below the (z-index of after)*/
    /*Example: (z-index of before) < (z-index of after) or 9998 < 9999*/
    z-index:9998;
}

.mainBox:after {
    content:"";
    position: absolute;
    right: 75px;
    top: -4px; /*suppose to be identical to border-width*/
    width: 0;
    height: 0;
    border-style: solid;
    border-width: 0 4px 4px 4px;
    border-color: transparent transparent #fff transparent; 
    z-index:9999;
}

The basic rules are:

The before right value must be calculated with: (after's top) - (before's top) = (before's right)

example: (-4px) - (-7px) = 3px

The before and after's top value must be identical to border-width.

The border color 3rd (#e0e0e0 in the example) value must be identical to its parent border color.

The before's z-index must at least one below the after's z-index.

example: (before's z-index) < (after's z-index) or 9998 < 9999.

The result:

回答5:

Use this online tool and you can do it without typing lot of code

http://www.cssarrowplease.com

回答6:

a.right{ border-style: dashed;
  border-color: transparent;
  border-width: 0.53em;
  display: -moz-inline-box;
  display: inline-block;
  font-size: 100px;
  height: 0;
  line-height: 0;
  position: relative;
  vertical-align: middle;
  width: 0; border-left-width: 1em;
  border-left-style: solid;
  border-left-color: #666;
  left: 0.25em; }

the above code can be used for right arrow.

回答7:

You can make use of span if u don't want to use a div.

span#pointer{border:solid 10px transparent;border-right-color:#fff;position:absolute;margin:-85px 0 0 -20px;}

http://jsfiddle.net/SSKwn/

来源：https://stackoverflow.com/questions/6972191/how-to-make-a-box-with-arrow-in-css

标签

css

css3

css-shapes