单击更改图标，然后通过JavaScript添加CSS类

Question

我正在尝试制作可扩展的H3。 为此，我需要单击“加号”图像，单击时必须更改为“减号”图像，我需要在h3中添加css类以显示内容。 我将粘贴以下所有代码：

<div class="default">
    [ManageBlog]
    <div class="msearch-result" id="LBSearchResult[moduleid]" style="display: none">
    </div>
    <div class="head">
        <h1 class="blogname">
                [BlogName] <img src="/portals/40/Images/Train_Fitness_2015_S/images/plus_symbol.png" alt="Plus Button" id="ExpandBlogDescriptionImg"></h1> [RssFeeds]
        <br style="line-height: 12px; clear: both" />
        <h3 class="blogdescription">
                [BlogDescription]</h3> [Author]
    </div>
    <br /> [Posts] [Pager]
</div>
<div style="clear: both"></div>

这是javascript：

jQuery(document).ready(function() {
     $("#ExpandBlogDescriptionImg").click(function() {
         var right = "https://train.fitness/portals/40/Images/Train_Fitness_2015_S/images/plus_symbol.png";
         var left = "https://train.fitness/portals/40/Images/Train_Fitness_2015_S/images/minus_symbol.png";
         element.src = element.bln ? right : left;
         element.bln = !element.bln;
     });
     var img = $("#ExpandBlogDescriptionImg");
     if (img.src = "https://train.fitness/portals/40/Images/Train_Fitness_2015_S/images/minus_symbol.png") {
         $('.blogdescription').addClass("ExpandBlogDescriptionText");
     } else {
         $('.blogdescription').removeClass("ExpandBlogDescriptionText");
     };
 });

Answer 1

您可以使用jquery的.attr函数来设置图像源，例如

$('.img-selector').attr('src','plusorminusimagepath.jpg');

您可以使用布尔标志来知道它是更少还是更多

Answer 2

在这里，我正在单击更改图像标签的alt属性。 用相同的方法可以更改src

  jQuery(document).ready(function() { $("#ExpandBlogDescriptionImg").click(function() { if ($(this).attr("alt") == "+") { $(this).attr("alt", "-"); } else { $(this).attr("alt", "+"); } }); var img = $("#ExpandBlogDescriptionImg"); if (img.src = "https://train.fitness/portals/40/Images/Train_Fitness_2015_S/images/minus_symbol.png") { $('.blogdescription').addClass("ExpandBlogDescriptionText"); } else { $('.blogdescription').removeClass("ExpandBlogDescriptionText"); }; }); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <div class="default"> [ManageBlog] <div class="msearch-result" id="LBSearchResult[moduleid]" style="display: none"> </div> <div class="head"> <h1 class="blogname"> [BlogName] <img alt="+" src="/portals/40/Images/Train_Fitness_2015_S/images/plus_symbol.png" alt="Plus Button" id="ExpandBlogDescriptionImg"></h1> [RssFeeds] <br style="line-height: 12px; clear: both" /> <h3 class="blogdescription"> [BlogDescription]</h3> [Author] </div> <br />[Posts] [Pager] </div> <div style="clear: both"></div> 

Answer 3

$("#ExpandBlogDescriptionImg").click( function(e){
    var right = "https://train.fitness/portals/40/Images/Train_Fitness_2015_S/images/plus_symbol.png";
    var left = "https://train.fitness/portals/40/Images/Train_Fitness_2015_S/images/minus_symbol.png";
    if($(e.currentTarget).attr('img') == left){ 
      $(this).hide();
      $(e.currentTarget).attr('img',right);
    }else{
      $(this).show();
      $(e.currentTarget).attr('img',left);
    }
});

Answer 4

您应该使用Sprite图片和CSS，否则当您单击它将加载另一个图片时，图片之间的一段时间会消失。

的HTML

<div class="head">
        <h1 class="blogname">
            [BlogName] <span class="plus icon"></span></h1>
        [RssFeeds]
        <br style="line-height: 12px; clear: both" />
        <h3 class="blogdescription">
            [BlogDescription]</h3>
        [Author]</div>
    <br />

的CSS

.icon{
   width:30px;
   height:30px;
   display:inline-block;
   background-image:url(plus-minus-sprite-image.png);
}
.icon.plus{
   background-position:20px center;
}
.icon.minus{
   background-position:40px center;
}

JS

$('.icon').click(function(){
     $(this).toggleClass("plus minus");

     if($(this).hasClass("plus")){
         $('.blogdescription').addClass("ExpandBlogDescriptionText");   
     }else{
         $('.blogdescription').removeClass("ExpandBlogDescriptionText");
     }
     // Or $('.blogdescription').toggleClass("ExpandBlogDescriptionText");
});