用表情符号制作的QR码

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There are lots of ASCII block characters, but none are specifically marked as white / empty. Additionally, some fonts don’t make the characters pure squares.

These characters are from the Unicode block “Geometric Shapes”. When paired with ️Variation Selector-16, they are given an Emoji presentation.

The above QR code is styled with "line-height:1em;" to make sure there are no vertical gaps between characters, and "letter-spacing:-3px;" to squash any horizontal gaps.

I was having a discussion with someone about the limitations of text based communication. How do you send a QR in, say, an email when you aren’t allowed to attach anything? We were looking at a text only system which wouldn’t allow attachments or BASE64 encoded inline.

So I knocked up a quick scrap of code to see if it would work with Emoji. It sort of works – but only if you can control the exact layout. On mobile screens, it might be too narrow, and you can’t easily control the character spacing.

The smallest possible QR code is 21×21 pixels, that’s too many characters to fit into a Tweet. Sorry!

您可以将其发布在类似Mastodon的网站上，但如果没有细粒度的CSS控件，则可能无法读取。