在 Typescript 中创建警报但警报不起作用的问题

Question

我正在使用打字稿创建一个闹钟，但遇到了问题。当时间过去时，我不会感到惊慌。我从 HTML 页面获取了三个输入——小时、分钟和秒。

之后我加上它们并减去当前时间。

    let h = <HTMLInputElement>document.getElementById("h");//getting input values of hour and ...
    let m = <HTMLInputElement>document.getElementById("m");
    let s = <HTMLInputElement>document.getElementById("s");

    let h1 = parseFloat(h.value);//converting the input values from string to float
    let m1 = parseFloat(m.value);
    let s1 = parseFloat(s.value);

    var rHours = new Date().getHours();
    var rMinutes = new Date().getMinutes();
    var rSeconds = new Date().getMinutes();
    var calc = (h1) + (m1) + (s1) - rHours - rMinutes - rSeconds;
    
    if(calc<=0){
       alert("Alarm");
    }
}

但是不能正常使用。

Answer 1

我已经有一段时间没有制作倒数计时器了，所以我想我ddo 只是为了好玩。这不是特别的 Typescript，但它在编译器中确实运行很好（参见下面的 link）。它是常规 JS，因此它也会在代码段中显示运行。我认为它可能会帮助您了解倒数计时器的工作原理。您的代码没有反映任何类型的倒计时，并且您确定经过时间的方法不正确。

为了演示的目的，我将 h1、m1 和 s1 设置为动态地从片段为运行时起 1 分钟。您可以轻松地调整它以根据您的输入元素工作。

document.querySelector('p span').innerHTML = new Date().toString()

function startCountdown() {
/* In your code uncomment this section...
    let el_h = <HTMLInputElement>document.getElementById("h");
    let el_m = <HTMLInputElement>document.getElementById("m");
    let el_s = <HTMLInputElement>document.getElementById("s");
*/

  // in your code comment out these lines and use yours from above instead (for typescript typing)
  let el_h = document.getElementById("h");
  let el_m = document.getElementById("m");
  let el_s = document.getElementById("s");


  let h1 = parseFloat(el_h.value);
  let m1 = parseFloat(el_m.value);
  let s1 = parseFloat(el_s.value);


  //const [h1, m1, s1] = ( (new Date().getHours() ) + ":" + (new Date().getMinutes() + 2) + ":" + new Date().getSeconds()).split(":");

  // get todays date
  let today = new Date().getFullYear() + "-" + (new Date().getMonth() + 1) + "-" + new Date().getDate();

  // add on the hours from the inputs
  today += " " + h1 + ":" + m1 + ":" + s1;
  const myTime = new Date(today);

  console.log('countdown to:', myTime, 'from:', new Date());
  const interval = setInterval(() => {
    let diff = (myTime.getTime() - new Date().getTime()) / 1000; // seconds
    let h = Math.floor(diff / 3600);
    let m = Math.floor(diff / 60 % 60);
    let s = Math.floor(diff % 60)
    console.log(h + " hours, " + m + " minutes, " + s + " seconds")
    if (diff <= 0) {
      clearInterval(interval);
      console.log("ALARM");
    }
  }, 1000)
}

<p>Cur time: <span></span></p>
<input id='h' placeholder='Hour (military time)'><input id='m' placeholder='Minute'><input id='s' placeholder='Seconds'><button onclick='startCountdown()'>Start</button>

tsplayground link

Answer 2

document.querySelector('p span').innerHTML = new Date().toString()

function startCountdown() {
/* In your code uncomment this section...
    let el_h = <HTMLInputElement>document.getElementById("h");
    let el_m = <HTMLInputElement>document.getElementById("m");
    let el_s = <HTMLInputElement>document.getElementById("s");
*/

  // in your code comment out these lines and use yours from above instead (for typescript typing)
  let el_h = document.getElementById("h");
  let el_m = document.getElementById("m");
  let el_s = document.getElementById("s");


  let h1 = parseFloat(el_h.value);
  let m1 = parseFloat(el_m.value);
  let s1 = parseFloat(el_s.value);


  //const [h1, m1, s1] = ( (new Date().getHours() ) + ":" + (new Date().getMinutes() + 2) + ":" + new Date().getSeconds()).split(":");

  // get todays date
  let today = new Date().getFullYear() + "-" + (new Date().getMonth() + 1) + "-" + new Date().getDate();

  // add on the hours from the inputs
  today += " " + h1 + ":" + m1 + ":" + s1;
  const myTime = new Date(today);

  console.log('countdown to:', myTime, 'from:', new Date());
  const interval = setInterval(() => {
    let diff = (myTime.getTime() - new Date().getTime()) / 1000; // seconds
    let h = Math.floor(diff / 3600);
    let m = Math.floor(diff / 60 % 60);
    let s = Math.floor(diff % 60)
    console.log(h + " hours, " + m + " minutes, " + s + " seconds")
    if (diff <= 0) {
      clearInterval(interval);
      console.log("ALARM");
    }
  }, 1000)
}

<p>Cur time: <span></span></p>
<input id='h' placeholder='Hour (military time)'><input id='m' placeholder='Minute'><input id='s' placeholder='Seconds'><button onclick='startCountdown()'>Start</button>

在 Typescript 中创建警报但警报不起作用的问题

Problem in creating an alarm in Typescript but the alarm isn't working

javascript

html

typescript

clock