我需要的信息在一个元标签中。当属性=“视频”时,我如何访问元标签的“内容”数据?
HTML:
<meta property="video" content="http://video.com/video33353.mp4" />
我需要的信息在一个元标签中。当属性=“视频”时,我如何访问元标签的“内容”数据?
HTML:
<meta property="video" content="http://video.com/video33353.mp4" />
当前回答
document.head.querySelector(“元[属性=视频]”).content;
其他回答
这个代码适用于我
<meta name="text" property="text" content="This is text" />
<meta name="video" property="text" content="http://video.com/video33353.mp4" />
JS
var x = document.getElementsByTagName("META");
var txt = "";
var i;
for (i = 0; i < x.length; i++) {
if (x[i].name=="video")
{
alert(x[i].content);
}
}
示例:http://jsfiddle.net/muthupandiant/ogfLwdwt/
如果您对获得所有元标记的更深远的解决方案感兴趣,可以使用这段代码
function getAllMetas() {
var metas = document.getElementsByTagName('meta');
var summary = [];
Array.from(metas)
.forEach((meta) => {
var tempsum = {};
var attributes = meta.getAttributeNames();
attributes.forEach(function(attribute) {
tempsum[attribute] = meta.getAttribute(attribute);
});
summary.push(tempsum);
});
return summary;
}
// usage
console.log(getAllMetas());
下面是一个函数,它将返回任何元标记的内容并记住结果,避免不必要的DOM查询。
var getMetaContent = (function(){
var metas = {};
var metaGetter = function(metaName){
var theMetaContent, wasDOMQueried = true;;
if (metas[metaName]) {
theMetaContent = metas[metaName];
wasDOMQueried = false;
}
else {
Array.prototype.forEach.call(document.getElementsByTagName("meta"), function(el) {
if (el.name === metaName) theMetaContent = el.content;
metas[metaName] = theMetaContent;
});
}
console.log("Q:wasDOMQueried? A:" + wasDOMQueried);
return theMetaContent;
}
return metaGetter;
})();
getMetaContent("description"); /* getMetaContent console.logs the content of the description metatag. If invoked a second time it confirms that the DOM was only queried once */
下面是一个扩展版本,它也可以查询打开的图形标签,并使用array# some:
var getMetaContent = (function(){
var metas = {};
var metaGetter = function(metaName){
wasDOMQueried = true;
if (metas[metaName]) {
wasDOMQueried = false;
}
else {
Array.prototype.some.call(document.getElementsByTagName("meta"), function(el) {
if(el.name === metaName){
metas[metaName] = el.content;
return true;
}
if(el.getAttribute("property") === metaName){
metas[metaName] = el.content;
return true;
}
else{
metas[metaName] = "meta tag not found";
}
});
}
console.info("Q:wasDOMQueried? A:" + wasDOMQueried);
console.info(metas);
return metas[metaName];
}
return metaGetter;
})();
getMetaContent("video"); // "http://video.com/video33353.mp4"
供参考,根据https://developer.mozilla.org/en-US/docs/Web/HTML/Element/meta全局属性是有效的,这意味着id属性可以与getElementById一起使用。
如果你使用JQuery,你可以使用:
$("meta[property='video']").attr('content');