You can apply this CSS to the inner <div>
:
#inner {
width: 50%;
margin: 0 auto;
}
Of course, you don't have to set the width
to 50%
. Any width less than the containing <div>
will work. The margin: 0 auto
is what does the actual centering.
If you are targeting Internet Explorer 8 (and later), it might be better to have this instead:
#inner {
display: table;
margin: 0 auto;
}
It will make the inner element center horizontally and it works without setting a specific width
.
Working example here:
#inner {
display: table;
margin: 0 auto;
border: 1px solid black;
}
#outer {
border: 1px solid red;
width:100%
}
<div id="outer">
<div id="inner">Foo foo</div>
</div>
EDIT
With flexbox
it is very easy to style the div horizontally and vertically centered.
#inner {
border: 1px solid black;
}
#outer {
border: 1px solid red;
width:100%;
display: flex;
justify-content: center;
}
<div id="outer">
<div id="inner">Foo foo</div>
</div>
To align the div vertically centered, use the property align-items: center
.
With HTML5 you can make file uploads with Ajax and jQuery. Not only that, you can do file validations (name, size, and MIME type) or handle the progress event with the HTML5 progress tag (or a div). Recently I had to make a file uploader, but I didn't want to use Flash nor Iframes or plugins and after some research I came up with the solution.
The HTML:
<form enctype="multipart/form-data">
<input name="file" type="file" />
<input type="button" value="Upload" />
</form>
<progress></progress>
First, you can do some validation if you want. For example, in the .on('change')
event of the file:
$(':file').on('change', function () {
var file = this.files[0];
if (file.size > 1024) {
alert('max upload size is 1k');
}
// Also see .name, .type
});
Now the $.ajax()
submit with the button's click:
$(':button').on('click', function () {
$.ajax({
// Your server script to process the upload
url: 'upload.php',
type: 'POST',
// Form data
data: new FormData($('form')[0]),
// Tell jQuery not to process data or worry about content-type
// You *must* include these options!
cache: false,
contentType: false,
processData: false,
// Custom XMLHttpRequest
xhr: function () {
var myXhr = $.ajaxSettings.xhr();
if (myXhr.upload) {
// For handling the progress of the upload
myXhr.upload.addEventListener('progress', function (e) {
if (e.lengthComputable) {
$('progress').attr({
value: e.loaded,
max: e.total,
});
}
}, false);
}
return myXhr;
}
});
});
As you can see, with HTML5 (and some research) file uploading not only becomes possible but super easy. Try it with Google Chrome as some of the HTML5 components of the examples aren't available in every browser.
Best Answer
You should be able to omit the
*
, but if I recall correctly, depending on which jQuery version you’re using, this might give faulty results.Note that for compatibility with the Selectors API (
document.querySelector{,all}
), the quotes around the attribute value (22
) may not be omitted in this case.Also, if you work with data attributes a lot in your jQuery scripts, you might want to consider using the HTML5 custom data attributes plugin. This allows you to write even more readable code by using
.dataAttr('foo')
, and results in a smaller file size after minification (compared to using.attr('data-foo')
).