某些元素的角度设置计时器

Question

这里我有一些jspdf函数

  public captureScreen() {
    // Start from here 
    this.loading = true;

    const data = document.getElementById('convert');
      html2canvas(data).then(canvas => {
      const imgWidth = 208;
      const pageHeight = 295;
      const imgHeight = canvas.height * imgWidth / canvas.width;
      const heightLeft = imgHeight;
      const contentDataURL = canvas.toDataURL('image/png');
      const pdf = new jspdf('p', 'mm', 'a4');
      const position = 0;
      pdf.addImage(contentDataURL, 'PNG', 0, position, imgWidth, imgHeight);
      pdf.save('Test.pdf');
      // Until here
      this.loading = false;
    });
  }

我想让这个函数运行一秒钟，直到它再次将this.loading返回为false。我怎样才能让一个计时器在执行最后一段代码之前设置2-3秒？

Answer 1

使用set timeout函数延迟几秒钟

// When calling function
this.loading = true;
setTimeout(function() { captureScreen(); }, 3000);

public captureScreen() {
    const data = document.getElementById('convert');
      html2canvas(data).then(canvas => {
      const imgWidth = 208;
      const pageHeight = 295;
      const imgHeight = canvas.height * imgWidth / canvas.width;
      const heightLeft = imgHeight;
      const contentDataURL = canvas.toDataURL('image/png');
      const pdf = new jspdf('p', 'mm', 'a4');
      const position = 0;
      pdf.addImage(contentDataURL, 'PNG', 0, position, imgWidth, imgHeight);
      pdf.save('Test.pdf');
      // Until here
      this.loading = false;
    });
}