javascript - 每小时调用一个函数(Call a function every hour)

Question

I am trying to update information from a weather service on my page.(我正在尝试更新页面上的气象服务信息。)

The info should be updated every hour on the hour.(该信息应每小时更新一次。) How exactly do I go about calling a function on the hour every hour?(我该如何每小时每小时精确地调用一个函数？) I kind of had an idea but im not sure of how to actually refine it so it works... What I had in mind was something like creating an if statement, such as: (pseudo code)(我有点主意，但是我不确定如何真正地对其进行改进……我想到的就是创建一个if语句，例如：（伪代码）) //get the mins of the current time var mins = datetime.mins(); if(mins == "00"){ function(); }   ask by user2961971 translate from so

Answer 1

You want to check out setInterval : https://developer.mozilla.org/en-US/docs/Web/API/Window.setInterval(您想检出setInterval ： https : //developer.mozilla.org/en-US/docs/Web/API/Window.setInterval)

It's a little hard to tell what you're trying to call with your code, but it would be something in the form of:(很难说出您要用代码调用什么，但这将是以下形式：) function callEveryHour() { setInterval(yourFunction, 1000 * 60 * 60); } If you want it every hour, try something like:(如果您希望每小时进行一次，请尝试以下操作：) var nextDate = new Date(); if (nextDate.getMinutes() === 0) { // You can check for seconds here too callEveryHour() } else { nextDate.setHours(nextDate.getHours() + 1); nextDate.setMinutes(0); nextDate.setSeconds(0);// I wouldn't do milliseconds too ;) var difference = nextDate - new Date(); setTimeout(callEveryHour, difference); } Now, this implementation checks the time once, sets the delay (or calls the function immediately), and then relies on setInterval to keep track after that.(现在，此实现检查一次时间，设置延迟（或立即调用函数），然后依靠setInterval跟踪此时间。) An alternative approach may be to poll the time every x many seconds/minutes, and fire it .getMinutes() == 0 instead (similar to the first part of the if-statement), which may sacrifice (marginal) performance for (marginal) accuracy.(另一种方法是每隔x秒钟/分钟轮询一次时间，然后将其.getMinutes() == 0 （类似于if语句的第一部分），这可能会牺牲（边际）性能（边际） ） 准确性。) Depending on your exact needs, I would play around with both solutions.(根据您的确切需求，我会同时考虑两种解决方案。)