// 触发图片
        open(url) {
            let _this = this;

            this.setAvatarBase64(url, (base64) => {
                _this.options.img = base64;
            });
        },

        // 设置头像base64
        setAvatarBase64(src, callback) {
            let _this = this;
            let image = new Image();
            // 处理缓存
            image.src = src + '?v=' + Math.random();
            // 支持跨域图片
            image.crossOrigin = "*";
            image.onload = function () {
                let base64 = _this.transBase64FromImage(image);
                callback && callback(base64);
            }
        },
        
        // 将网络图片转换成base64格式
        transBase64FromImage(image) {
            let canvas = document.createElement("canvas");
            canvas.width = image.width;
            canvas.height = image.height;
            let ctx = canvas.getContext("2d");
            ctx.drawImage(image, 0, 0, image.width, image.height);
            // 可选其他值 image/jpeg
            return canvas.toDataURL("image/png");
        }