js下載圖片

   DownloadImgZP = imgPath => {
        const image = new Image();
        // 解決跨域 Canvas 污染問題
        image.setAttribute('crossOrigin', 'anonymous');
        image.onload = function() {
            const canvas = document.createElement('canvas');
            canvas.width = image.width;
            canvas.height = image.height;
            const context = canvas.getContext('2d');
            context.drawImage(image, 0, 0, image.width, image.height);
            const url = canvas.toDataURL('image/png'); // 獲得圖片的base64編碼數據
            const a = document.createElement('a'); // 生成一個a元素
            const event = new MouseEvent('click'); // 建立一個單擊事件
            a.download = 'img.png' || 'photo'; // 設置圖片名稱
            a.href = url; // 將生成的URL設置爲a.href屬性
            a.dispatchEvent(event); // 觸發a的單擊事件
        };
        image.src = imgPath;
    };