await html2canvas(getById("winyh"), {

        height:500,

        allowTaint: true,

        useCORS: true,

      }).then((canvas) => {

        let base64url = canvas.toDataURL('image/jpeg', 1.0 );

        // document.body.appendChild(canvas);

      });

base64url 就是 待上传到服务端的 url