防止JavaScript函数运行两次(setTimeout) [英] Prevent JavaScript function from running twice (setTimeout)
问题描述
我具有使用setTimeout
可以运行几秒钟的功能.单击按钮后将运行此功能.
I have this function that runs for several seconds with the use of setTimeout
. This function is ran when a button is clicked.
function complete() {
var div = document.getElementById('log');
setTimeout(function(){ div.innerHTML = div.innerHTML + intro[Math.floor(Math.random() * intro.length)] + "<br>"; }, 500);
setTimeout(function(){ div.innerHTML = div.innerHTML + second[Math.floor(Math.random() * second.length)] + "<br>"; }, 2560);
setTimeout(function(){ div.innerHTML = div.innerHTML + third[Math.floor(Math.random() * third.length)] + "<br>"; }, 4860);
setTimeout(function(){ div.innerHTML = div.innerHTML + fourth[Math.floor(Math.random() * fourth.length)] + "<br>"; }, 7860);
setTimeout(function(){ div.innerHTML = div.innerHTML + fifth[Math.floor(Math.random() * fifth.length)] + "<br>"; }, 9640);
}
但是,如果用户多次单击按钮,此功能也会开始执行多次.我试图通过使用下面的代码来防止这种情况的发生,但是,它无法正常工作.
However, if the user clicks the button multiple times, this function begins to excute multiple times as well. I have tried to prevent this from occuring by using the code below, however, it is not working.
var running;
function complete() {
if (running == true) { alert('error'); }
running = true;
var div = document.getElementById('log');
setTimeout(function(){ div.innerHTML = div.innerHTML + intro[Math.floor(Math.random() * intro.length)] + "<br>"; }, 500);
setTimeout(function(){ div.innerHTML = div.innerHTML + second[Math.floor(Math.random() * second.length)] + "<br>"; }, 2560);
setTimeout(function(){ div.innerHTML = div.innerHTML + third[Math.floor(Math.random() * third.length)] + "<br>"; }, 4860);
setTimeout(function(){ div.innerHTML = div.innerHTML + fourth[Math.floor(Math.random() * fourth.length)] + "<br>"; }, 7860);
setTimeout(function(){ div.innerHTML = div.innerHTML + fifth[Math.floor(Math.random() * fifth.length)] + "<br>"; }, 9640);
running = false;
}
我应该采用哪种方法,或者如何解决我的代码,以便它可以完成我想做的事情?
What approach should I take, or how can I fix my code so it can accomplish what I am trying to do?
推荐答案
您的running = false;
应该在超时功能内,因为超时将异步执行,running = false;
将在超时结束之前执行
Your running = false;
should be inside timeout function, as timeout will execute asyncronically, the running = false;
will execute before your timeout ends
一个简单的例子是
var running = false,
div = document.getElementById('response'),
limit = 5,
current = 0;
$('#trigger').click(function () {
if (running === true) {
alert('Error: The cycle was running. Aborting.');
running = false;
return false;
}
running = true;
var end = setInterval(function () {
if (current >= limit || running == false) {
running = false;
clearInterval(end);
}
div.innerHTML += 'Hello World<br />';
current++;
}, 500);
});
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