write a piece of code that generates a QR code on a single page and take effect normally:
:
canvas is empty, who has encountered this situation
write a piece of code that generates a QR code on a single page and take effect normally:
:
canvas is empty, who has encountered this situation
maybe the pop-up window didn't render, and you can't find the dom of canvas. Add a settimeout 0 to try
, but I'm a little confused. Add a timer in that place
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