保存图片文件,下载图片

    function downloadIamge(imgsrc, name) { //下载图片地址和图片名
        let image = new Image();
        // 解决跨域 Canvas 污染问题
        image.setAttribute("crossOrigin", "anonymous");
        image.onload = function () {
            let canvas = document.createElement("canvas");
            canvas.width = image.width;
            canvas.height = image.height;
            let context = canvas.getContext("2d");
            context.drawImage(image, 0, 0, image.width, image.height);
            let url = canvas.toDataURL("image/png"); //得到图片的base64编码数据
            let a = document.createElement("a"); // 生成一个a元素
            let event = new MouseEvent("click"); // 创建一个单击事件
            a.download = name || "photo"; // 设置图片名称
            a.href = url; // 将生成的URL设置为a.href属性
            a.dispatchEvent(event); // 触发a的单击事件
        };
        image.src = imgsrc;
    }