the requirement is to implement compressed upload. Most of them are realized by canvas method on the Internet, so I wrote one after it. But it doesn"t seem to work. After uploading, the downloaded picture is still very large.
the code is as follows
html5Reader(file, item){
const reader = new FileReader();
let Img = new Image();
let newImageData;
Img.src = window.URL.createObjectURL(file);
Img.onload = (e) => {
let canvas = document.createElement("canvas");
let ctx = canvas.getContext("2d");
canvas.width = Img.width;
canvas.height = Img.height;
ctx.drawImage(Img, 0, 0, canvas.width, canvas.height);
newImageData = canvas.toDataURL("image/jpeg", 0.1);
console.log(newImageData)
this.$set(item, "src", newImageData);
};
},