// 上传前判断
    public async beforeUpload(file: any) {
        const is1M = file.size / 1024 / 1024 < 3; // 限制小于3M
        if (!is1M) {
            this.$message.error('图片尺寸限制最小为270 x 270，大小不可超过3MB，比例为1:1');
            return false;
        } else {
            const isSize = new Promise((resolve, reject) => {
                const width = 270;
                const height = 270;
                const _URL = window.URL || window.webkitURL;
                const img = new Image();
                img.onload = () => {
                    const valid = img.width >= width && img.height >= height && img.width === img.height;
                    valid ? resolve() : reject();
                };
                img.src = _URL.createObjectURL(file);
            }).then(
                () => {
                    return file;
                },
                () => {
                    this.$message.error('图片尺寸限制最小为270 x 270，大小不可超过3MB，比例为1:1');
                    return Promise.reject();
                },
            );
            return isSize;
        }
    }

看了很多还不如自己撸一个