手机微信端js图片插件下载

function downloadImage(imageUrl, imageName) {
    // 创建一个Image对象
    var image = new Image();
    image.crossOrigin = "Anonymous"; // 解决跨域问题

    image.onload = function() {
        // 创建canvas元素
        var canvas = document.createElement('canvas');
        canvas.width = this.naturalWidth;
        canvas.height = this.naturalHeight;
        // 将图片绘制到canvas上
        var ctx = canvas.getContext('2d');
        ctx.drawImage(this, 0, 0);

        // 将canvas转换为Blob对象
        canvas.toBlob(function(blob) {
            // 创建一个指向Blob对象的URL
            var url = URL.createObjectURL(blob);
            // 创建a标签并设置属性
            var a = document.createElement('a');
            a.href = url;
            a.download = imageName || 'downloaded_image.jpg';
            // 模拟点击a标签触发下载
            document.body.appendChild(a);
            a.click();
            // 清理
            document.body.removeChild(a);
            URL.revokeObjectURL(url);
        });
    };

    image.src = imageUrl;
}

// 使用示例
downloadImage('https://example.com/image.jpg', 'my_image.jpg');