Javascript 如果存在多个元素,如何使用jQuery选择器指向正确的元素?
使用jQuery选择器在html中选择元素时遇到困难。我正在创建一个带有复选框和视频标签的分类过滤器。我试图找出如何为每个基于其视频标签显示/隐藏的视频缩略图元素以及是否选中复选框都具有唯一标识符。我有一个函数,它基本上从另一个函数获取视频标签,该函数循环遍历每个视频并提取其标签数组值,如下所示:Javascript 如果存在多个元素,如何使用jQuery选择器指向正确的元素?,javascript,jquery,html,jquery-selectors,youtube-api,Javascript,Jquery,Html,Jquery Selectors,Youtube Api,使用jQuery选择器在html中选择元素时遇到困难。我正在创建一个带有复选框和视频标签的分类过滤器。我试图找出如何为每个基于其视频标签显示/隐藏的视频缩略图元素以及是否选中复选框都具有唯一标识符。我有一个函数,它基本上从另一个函数获取视频标签,该函数循环遍历每个视频并提取其标签数组值,如下所示: // print the results function(data) { var output; $.each(da
// print the results
function(data)
{
var output;
$.each(data.items,
function(i, item)
{
var vidTitle = item.snippet.title; // video title
var vidDesc = item.snippet.description; // video description
var videoId = item.snippet.resourceId.videoId; // video id
var vidThumbUrl = item.snippet.thumbnails.default.url; // video thumbnail url
getVideoDuration(videoId).done(function(duration, view/*, tags*/)
{
vidDuration = duration;
viewCount = view;
//vidTags = tags;
// check if video tags is empty or undefined
if(typeof videoTags === 'undefined' || videoTags == "" || videoTags === null)
{
videoTags = "No tags have been defined for this video.";
}
// check input categories
validateCategory(videoTags);
console.log("id: " + videoId + " duration: " + convert_time(vidDuration) + " viewCount: " + viewCount + ' videoTags: ' + videoTags); // return value in console
//console.log(JSON.stringify(item));
console.log("<br>");
output = '<li><iframe height="' + vidHeight + '" width="' + vidWidth + '" src=\"//www.youtube.com/embed/' + videoId + '\"></iframe></li><div id="title">' + vidTitle + '</div><div id="desc">' + vidDesc + '</div><div id="duration">Length: ' + convert_time(vidDuration) + '</div><div id="stats">View Count: ' + viewCount + '</div><div id="tags">Tags: ' + videoTags + '</div>';
// if video title is longer than 25 characters, insert the three-dotted ellipse
if(vidTitle.length > 25)
{
var strNewVidTitle = vidTitle.substr(0, 25) + "...";
vidTitle = strNewVidTitle;
}
var vidThumbnail = '<div class="video-thumbnail"><a target="_blank" href="https://www.youtube.com/watch?v=' + videoId + '"><div class="video-overlay"><img src="imgs/video-play-button.png"/></div><img id="thumb" src="' + vidThumbUrl + '" alt="No Image Available." style="width:204px;height:128px"/></a><p><a target="_blank" href="https://www.youtube.com/watch?v=' + videoId + '">' + vidTitle + '</a><br/>' + convert_time(vidDuration) + ' / Views: ' + viewCount + '</p></div>';
// append results
$('#results').append(output);
$('#thumb').append(vidThumbnail);
}); // end of getVideoDuration(videoId).done
}
); // end of getViewCount(videoId).done
}
HTML:
<div id="container">
<h1>Youtube Videos</h1>
<ul id="results"></ul>
<hr/>
<h1>Thumbnails</h1>
<div id="thumb"></div>
<div id="category-list" class="getFixed">
<h1>Categories</h1>
<input class="categories" type="checkbox" name="filter" value="Reading" checked>Reading<br/>
<input class="categories" type="checkbox" name="filter" value="Math" checked>Math<br/>
<input class="categories" type="checkbox" name="filter" value="Science" checked>Science
</div>
</div>
Youtube视频
缩略图
类别
阅读
数学
科学类
validateCategory(…)
函数将成功循环,但它不会引用jQuery选择器使用这个视频缩略图类来显示/隐藏类别中的特定视频,就像类别过滤器一样。我甚至做了背景色和可见性,但都不起作用。我正在试图找出如何将这两个和这两个链接在一起。它看起来像是此
指的是窗口中的对象,它位于validateCategory()
函数中。窗口对象没有直接访问dom的权限,因此您需要使用this.document
或只使用document
。但是,我认为您不想在本例中引用整个文档。这样做将在每次迭代中对.video thumbnail
类的每个成员进行更改。我认为您应该在为每个条目构建vidjumblynail div
后调用此函数,并将此div作为参数传递:
function(data)
{
var output;
$.each(data.items,
function(i, item)
{
var vidTitle = item.snippet.title; // video title
var vidDesc = item.snippet.description; // video description
var videoId = item.snippet.resourceId.videoId; // video id
var vidThumbUrl = item.snippet.thumbnails.default.url; // video thumbnail url
getVideoDuration(videoId).done(function(duration, view/*, tags*/)
{
vidDuration = duration;
viewCount = view;
//vidTags = tags;
// check if video tags is empty or undefined
if(typeof videoTags === 'undefined' || videoTags == "" || videoTags === null)
{
videoTags = "No tags have been defined for this video.";
}
console.log("id: " + videoId + " duration: " + convert_time(vidDuration) + " viewCount: " + viewCount + ' videoTags: ' + videoTags); // return value in console
//console.log(JSON.stringify(item));
console.log("<br>");
output = '<li><iframe height="' + vidHeight + '" width="' + vidWidth + '" src=\"//www.youtube.com/embed/' + videoId + '\"></iframe></li><div id="title">' + vidTitle + '</div><div id="desc">' + vidDesc + '</div><div id="duration">Length: ' + convert_time(vidDuration) + '</div><div id="stats">View Count: ' + viewCount + '</div><div id="tags">Tags: ' + videoTags + '</div>';
// if video title is longer than 25 characters, insert the three-dotted ellipse
if(vidTitle.length > 25)
{
var strNewVidTitle = vidTitle.substr(0, 25) + "...";
vidTitle = strNewVidTitle;
}
var vidThumbnail = '<div class="video-thumbnail"><a target="_blank" href="https://www.youtube.com/watch?v=' + videoId + '"><div class="video-overlay"><img src="imgs/video-play-button.png"/></div><img id="thumb" src="' + vidThumbUrl + '" alt="No Image Available." style="width:204px;height:128px"/></a><p><a target="_blank" href="https://www.youtube.com/watch?v=' + videoId + '">' + vidTitle + '</a><br/>' + convert_time(vidDuration) + ' / Views: ' + viewCount + '</p></div>';
// check input categories
validateCategory(videoTags, vidThumbnail);
// append results
$('#results').append(output);
$('#thumb').append(vidThumbnail);
}); // end of getVideoDuration(videoId).done
}
); // end of getViewCount(videoId).done
}
function validateCategory(videoTags, vidThumbnail) // TODO: add videoId to make an unique identifier for said video thumbnail.
{
// check if input category is or isn't checked and omit videos not matching checked categories
if($('input[value="reading"]').is(':checked'))
{
console.log('%c reading: ' + ".is(':checked'):", 'color:blue;'); // check if 'pregnancy' is checked
for(i = 0; i < videoTags.length; i++)
{
if(videoTags[i] === "reading".trim().toLowerCase())
{
$('.video-thumbnail', vidThumbnail).css({visibility:'visible'});
$('.video-thumbnail', vidThumbnail).show();
$('.video-thumbnail', vidThumbnail).attr('rel','reading'); // set rel attribute according to tag name as a unique identifier
$('.video-thumbnail', vidThumbnail).css({backgroundColor:'red'});
}
else
{
$('.video-thumbnail', vidThumbnail).css({visibility:'hidden'});
$('.video-thumbnail', vidThumbnail).hide();
}
}
}
else
{
$('.video-thumbnail', vidThumbnail).css({visibility:'hidden'});
$('.video-thumbnail', vidThumbnail).hide();
}
}
功能(数据)
{
var输出;
$。每个(数据项,
职能(一、项目)
{
var vidTitle=item.snippet.title;//视频标题
var vidDesc=item.snippet.description;//视频描述
var videoId=item.snippet.resourceId.videoId;//视频id
var vidThumbUrl=item.snippet.thumbnails.default.url;//视频缩略图url
getVideoDuration(videoId).done(函数(duration,view/*,tags*/)
{
持续时间=持续时间;
viewCount=视图;
//视频标签=标签;
//检查视频标签是否为空或未定义
如果(视频标签的类型=='undefined'| |视频标签==“”| |视频标签===null)
{
videoTags=“尚未为此视频定义任何标记。”;
}
log(“id:+videoId+”持续时间:“+convert_time(vidDuration)+”viewCount:“+viewCount+”videoTags:“+videoTags”);//在控制台中返回值
//log(JSON.stringify(item));
console.log(“
”);
输出=''+vidTitle+'+vidDesc+'长度:'+convert_时间(vidDuration)+'视图计数:'+viewCount+'标记:'+videoTags+'';
//如果视频标题超过25个字符,请插入三个点椭圆
如果(vidTitle.length>25)
{
var strNewVidTitle=vidTitle.substr(0,25)+“…”;
vidTitle=strNewVidTitle;
}
var vidThumbnail='
'+convert_time(vidDuration)+'/Views:'+viewCount+'';
//检查输入类别
validateCategory(视频标签、视频缩略图);
//附加结果
$(“#结果”)。追加(输出);
$('#thumb')。追加(vidThumbnail);
});//getVideoDuration(videoId)的结束。完成
}
);//getViewCount(videoId)结束。完成
}
函数validateCategory(videoTags,Vid缩略图)//TODO:添加videoId为所述视频缩略图创建唯一标识符。
{
//检查输入类别是否选中,并忽略与选中类别不匹配的视频
如果($('input[value=“reading”]”)是(':checked'))
{
console.log(“%c reading:”+“.is(“:checked”):”,“color:blue;”;//检查是否选中了“怀孕”
对于(i=0;i
它看起来像是此
引用了函数中的窗口
对象。窗口对象没有直接访问dom的权限,因此您需要使用this.document
或只使用document
。但是,我认为您不想在本例中引用整个文档。这样做将在每次迭代中对.video thumbnail
类的每个成员进行更改。我认为您应该在为每个条目构建vidjumblynail div
后调用此函数,并将此div作为参数传递:
function(data)
{
var output;
$.each(data.items,
function(i, item)
{
var vidTitle = item.snippet.title; // video title
var vidDesc = item.snippet.description; // video description
var videoId = item.snippet.resourceId.videoId; // video id
var vidThumbUrl = item.snippet.thumbnails.default.url; // video thumbnail url
getVideoDuration(videoId).done(function(duration, view/*, tags*/)
{
vidDuration = duration;
viewCount = view;
//vidTags = tags;
// check if video tags is empty or undefined
if(typeof videoTags === 'undefined' || videoTags == "" || videoTags === null)
{
videoTags = "No tags have been defined for this video.";
}
console.log("id: " + videoId + " duration: " + convert_time(vidDuration) + " viewCount: " + viewCount + ' videoTags: ' + videoTags); // return value in console
//console.log(JSON.stringify(item));
console.log("<br>");
output = '<li><iframe height="' + vidHeight + '" width="' + vidWidth + '" src=\"//www.youtube.com/embed/' + videoId + '\"></iframe></li><div id="title">' + vidTitle + '</div><div id="desc">' + vidDesc + '</div><div id="duration">Length: ' + convert_time(vidDuration) + '</div><div id="stats">View Count: ' + viewCount + '</div><div id="tags">Tags: ' + videoTags + '</div>';
// if video title is longer than 25 characters, insert the three-dotted ellipse
if(vidTitle.length > 25)
{
var strNewVidTitle = vidTitle.substr(0, 25) + "...";
vidTitle = strNewVidTitle;
}
var vidThumbnail = '<div class="video-thumbnail"><a target="_blank" href="https://www.youtube.com/watch?v=' + videoId + '"><div class="video-overlay"><img src="imgs/video-play-button.png"/></div><img id="thumb" src="' + vidThumbUrl + '" alt="No Image Available." style="width:204px;height:128px"/></a><p><a target="_blank" href="https://www.youtube.com/watch?v=' + videoId + '">' + vidTitle + '</a><br/>' + convert_time(vidDuration) + ' / Views: ' + viewCount + '</p></div>';
// check input categories
validateCategory(videoTags, vidThumbnail);
// append results
$('#results').append(output);
$('#thumb').append(vidThumbnail);
}); // end of getVideoDuration(videoId).done
}
); // end of getViewCount(videoId).done
}
function validateCategory(videoTags, vidThumbnail) // TODO: add videoId to make an unique identifier for said video thumbnail.
{
// check if input category is or isn't checked and omit videos not matching checked categories
if($('input[value="reading"]').is(':checked'))
{
console.log('%c reading: ' + ".is(':checked'):", 'color:blue;'); // check if 'pregnancy' is checked
for(i = 0; i < videoTags.length; i++)
{
if(videoTags[i] === "reading".trim().toLowerCase())
{
$('.video-thumbnail', vidThumbnail).css({visibility:'visible'});
$('.video-thumbnail', vidThumbnail).show();
$('.video-thumbnail', vidThumbnail).attr('rel','reading'); // set rel attribute according to tag name as a unique identifier
$('.video-thumbnail', vidThumbnail).css({backgroundColor:'red'});
}
else
{
$('.video-thumbnail', vidThumbnail).css({visibility:'hidden'});
$('.video-thumbnail', vidThumbnail).hide();
}
}
}
else
{
$('.video-thumbnail', vidThumbnail).css({visibility:'hidden'});
$('.video-thumbnail', vidThumbnail).hide();
}
}
功能(数据)
{
var输出;
$。每个(数据项,
职能(一、项目)
{
var vidTitle=item.snippet.tit