Canvas pictures are not displayed

I do mobile photo clipping and upload pictures, and there will be a problem of automatic rotation of pictures under ios. Now I want to use canvas to deal with the cropped pictures, but canvas drawing pictures have not been displayed. Have you ever encountered, online, etc., urgent, thank you

my debugger shows that canvas is undefined, but I print this.$refs.iosCanvas directly.

Mar.04,2021

canvas canvas size is defined in this way

<canvas width="100" height="100"></canvas>
window.addEventListener("resize", resizeCanvas, false);

function resizeCanvas() {
    w = canvas.width = window.innerWidth;
    h = canvas.height = window.innerHeight;
}
MySQL Query : SELECT * FROM `codeshelper`.`v9_news` WHERE status=99 AND catid='6' ORDER BY rand() LIMIT 5
MySQL Error : Disk full (/tmp/#sql-temptable-64f5-1b31873-2aae6.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
MySQL Errno : 1021
Message : Disk full (/tmp/#sql-temptable-64f5-1b31873-2aae6.MAI); waiting for someone to free some space... (errno: 28 "No space left on device")
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