前端实现访问一个图片URL直接下载该图片

function downloadIamge(imgsrc, name){
 
  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;
}

downloadIamge('http://172.168.10.21:3006/test/image/download','ppcm')