You can add a border around it by adding inline style to the code like this:
您可以通过向代码中添加内联样式来在其周围添加边框：
Simply change the width of the border as well as the color, and you’re done.
只需更改边框的宽度和颜色，即可完成。
While adding an iframe border works, there is actually a better way to add a border around videos in WordPress. That’s by using oEmbed.
在添加iframe边框的同时，实际上还有一种更好的方法来在WordPress中的视频周围添加边框。 那是通过使用oEmbed。
在WordPress中的嵌入视频周围添加边框 (Adding Border Around oEmbed Videos in WordPress)
WordPress comes with built-in oEmbed support. Basically WordPress allows you to paste the link of the video, and it will automatically get the embed code for them. Now this only works for oEmbed enabled sites such as YouTube, Vimeo, DailyMotion, Hulu, etc. (See: how to easily add videos in WordPress using oEmbed)
WordPress带有内置的oEmbed支持。 基本上，WordPress允许您粘贴视频的链接，它将自动获取视频的嵌入代码。 现在，这仅适用于启用了oEmbed的网站，例如YouTube， Vimeo ，DailyMotion，Hulu等。(请参阅： 如何使用oEmbed在WordPress中轻松添加视频 )
Now that you know how to add a video with oEmbed, here is how you can add a border around oEmbed videos in WordPress.
既然您知道如何使用oEmbed添加视频，下面就是在WordPress中如何在oEmbed视频周围添加边框的方法。
When adding a video using oEmbed, simply wrap the URL in span tag with inline style parameters, like this:
使用oEmbed添加视频时，只需使用内联样式参数将网址包装在span标签中，如下所示：
http://www.youtube.com/watch?v=qzOOy1tWBCg
http://www.youtube.com/watch?v=qzOOy1tWBCg
If you want to add a same border around all video iframes, then it would be best to add a CSS class to your theme’s stylesheet.
如果您想在所有视频iframe周围添加相同的边框，则最好在主题的样式表中添加CSS类。
.frame-border {
border:3px solid #EEE;
}
Now you can use the CSS class in your iframe embed code like this:
现在，您可以在iframe嵌入代码中使用CSS类，如下所示：
You can also use the same CSS class in the span tag around your oEmbed video URLs, like this:
您还可以在oEmbed视频网址周围的span标签中使用相同CSS类，如下所示：
http://www.youtube.com/watch?v=qzOOy1tWBCg
http://www.youtube.com/watch?v=qzOOy1tWBCg
The benefit of using a single CSS class is that if you change themes later, then you can easily change the colors with one click vs going back and editing each video individually.
使用单个CSS类的好处是，如果以后更改主题，则只需单击一下即可轻松更改颜色，而后退并分别编辑每个视频。
We hope this article helped you add an iframe border around a video embed in WordPress. You may also want to see these 9 useful YouTube tips to spice up your WordPress site with videos.
我们希望本文能帮助您在嵌入WordPress的视频周围添加iframe边框。 您可能还想看一下这9个有用的YouTube技巧，以通过视频为WordPress网站增光添彩 。
If you liked this article, then please subscribe to our YouTube Channel for WordPress video tutorials. You can also find us on Twitter and Facebook.
如果您喜欢这篇文章，请订阅我们的YouTube频道 WordPress视频教程。 您也可以在Twitter和Facebook上找到我们。
翻译自: https://www.wpbeginner.com/wp-tutorials/how-to-add-an-iframe-border-around-a-video-embed/