ng2-pdfjs-viewer的快捷键实现

Question

我已经实现了用于缩放，旋转顺时针，逆时针旋转的快捷键

它们工作正常，但每次按pdf键时都会刷新，这需要更长的时间

当我们点击工具栏中的选项时，加载时间不会很长

谁能让我知道原因和正确的方法

if (event.key == '+' && event.composedPath()[0]['localName'] != 'input' && event.composedPath()[0]['localName'] != 'textarea')
{
    let zoomvalue : number = +this.pdfViewer.zoom;
    zoomvalue = zoomvalue + 10;
    this.zoomInOrOut = zoomvalue.toString();

    this.pdfViewer.zoom = this.zoomInOrOut;
    this.pdfViewer.refresh();
}
else if (event.key == 'k' && event.ctrlKey == true && event.composedPath()[0]['localName'] != 'input' && event.composedPath()[0]['localName'] != 'textarea')
{
    if (this.pdfViewer.rotatecw == = true)
    {
        this.pdfViewer.rotatecw = false;
    }
    else
    {
        this.pdfViewer.rotatecw = true;
    }
    let pageIndex = this.pdfViewer.page;
    this.pdfViewer.page = pageIndex;
    this.pdfViewer.refresh();
}

与“-”相同，“ l”与缩小和逆时针旋转

如果this.pdfViewer.refresh();被删除，则更改不会得到反映

以正确的方法帮助我