Check if viewport zoomed

问题

Is there an easy way to check whether the user scaled the page (using pinch on mobile devices)?

Thought verge.js would help, but I don't know what I can compare viewportH with.

回答1:

You can compare the screen.width to the window.innerWidth. If the value is anything other than 1, the viewport has been zoomed.

viewportScale = screen.width / window.innerWidth;
alert(viewportScale);

References: https://developer.mozilla.org/en-US/docs/Web/API/Window.screen

https://developer.mozilla.org/en-US/docs/Web/API/window.innerWidth

回答2:

    (
        document.documentElement.clientWidth
    /   window.innerWidth
    )
>
    1

Only for mobile devices, though!

来源：https://stackoverflow.com/questions/19888098/check-if-viewport-zoomed