Wha开发者_如何学JAVAt's the fastest way possible to get a string like "fade" from the classes in the element below?

<div class="MyElement fx-fade"> ... </div>

If you wanted to look for something that ended in 'fade' you would use:

$("*[class$='fade']")

And for elements with a class that started with 'fade' you would use:

$("*[class^='fade']")

And to get elements that contain 'fade' you would use (this would be quicker than going through the class names string)

$("*[class*='fade']")

The * gets all elements so you could replace this with the element you wanted.

If you want elements that has a classname that starts with fx- you would do:

var classname = "";
var elArray = $("*[class*='fx-']");
    
for (var a = 0; a < elArray.length; a++) {
   // fade
    classname = elArray[a].split("-")[1]; 
}

The array used in the for loop would have all the elements with the classnames like 'fx-'.

Rather than than the for loop checking the elements for the correct class name.

More information at jquery.com

var classes = $('.MyElement').attr('class').split(' ');
for (var i = 0; i < classes.length; i++) {
  var matches = /^fx\-(.+)/.exec(classes[i]);
  if (matches != null) {
    var fxclass = matches[1];
  }
}

Try this:

$("div[class*='fade']")

More info

The question title and the question do not exactly match (title asks for prefix, question asks for suffix/partial)

1. Select elements by class-prefix

Combine following two jQuery/CSS selectors:

$( "[class^='fx-'],[class*=' fx-']" )

[class^='fx-'] Starts-With-Selector
Find elements where the first letters of the entire class attribute starts with "fx-"
e.g. <a class="fx-fade MyElement anything">
[class*=' fx-'] Contains-Selector
Find elements where a space + "fx-" is found anywhere inside the class attribute
e.g. <a class="MyElement fx-fade anything">

This selector makes sure, that you do not get false positives such as <a class="MyElement sfx-none">

2. Select elements by class-suffix

Almost identical to the prefix selector:

$( "[class$='-fade'],[class*='-fade ']" )

[class$='-fade'] End-With-Selector
Find elements where the last letters of the entire class attribute are with "-fade"
e.g. <a class="MyElement anything fx-fade">
[class*='-fade '] Contains-Selector
Find elements where a "-fade" + space is found anywhere inside the class attribute
e.g. <a class="anything fx-fade MyElement">

This selector makes sure, that you do not get false positives such as <a class="MyElement sfx-none">

3. Select elements by class-substring

When you need to find a substring that is neither the start nor the end of a class name, use the selector suggested in the other answers:

$( "[class*='fade']" )

[class*='fade'] Contains-Selector
Find elements where "fade" is found anywhere inside the class attribute
e.g. <a class="fx-fade-out">

Warning: This also finds "no-fade" or "faded". Use the Contains-Selector with care!

Check out JQuery selector regular expressions. It might be exactly what you need! :)

I'd probably go with something like:

//Split class list into individual classes:
var classes = $(".MyElement").attr("class").split(" ");
var fxType;

//Loop through them:
for (var i = 0, max = classes.elngth; i < max; i++) {
  var class = classes[i].split("-");
  //Check if the current one is prefixed with 'fx':
  if (class[0] == "fx") {
    //It is an FX - do whatever you want with it, the type of FX is stored in class[1], ie:
    fxType = class[1];
  }
}

This simple snippet we use in our sites:

/**
 * Script to load a popup container for share buttons
 *
 * Possible usage for Facebook, Twitter and Google:
 *
 * <a class="share-buttons-fb" href="https://www.facebook.com/sharer/sharer.php?u=<?php echo get_the_permalink(); ?>&title=<?php the_title(); ?>">Facebook</a>
 * <a class="share-buttons-twitter" href="https://twitter.com/intent/tweet?text=<?php the_title(); ?>: <?php echo get_the_permalink(); ?>">Twitter</a>
 * <a class="share-buttons-google" href="http://plus.google.com/share?url=<?php echo get_the_permalink(); ?>">Google+</a>
 */
jQuery(document).ready(function ($) {

    // Whenever an anchor with the class with share-button in it is clicked
    $("a[class*='share-button']").click(function () {
        // Variables to set the size of the popup container
        var windowWidth = 500;
        var windowHeight = 255;

        // Variables to set the position of the popup container
        var positionWindowLeft = (screen.width / 2) - (windowWidth / 2);
        var positionWindowTop = (screen.height / 3) - (windowHeight / 3);

        // Create new windows with the opening url of the href attribute of the anchor and the above variables
        var popupWindow = window.open($(this).prop('href'), '', 'scrollbars=no,menubar=no,status=no,titlebar=no,toolbar=nolocation=no,menubar=no,resizable=noe,height=' + windowHeight + ',width=' + windowWidth + ',top=' + positionWindowTop + ', left=' + positionWindowLeft);

        // If the default windows is focused
        if (window.focus) {
            // Change the focus to the the popup window
            popupWindow.focus();
        }

        return false;
    });
});