blocks|key|996223|text|您可以使用setTimeout或setInterval。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|996224|不同的是-+setTimeout只触发函数一次，然后您必须再次设置它。setInterval一次又一次地触发表达式，除非您告诉它停止|996225|entityMap^0|5|A|G|B|0|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@]|D|@]|E|$]]|$1|H|3|-4|5|6|7|P|8|@]|D|@]|E|$]]]|I|$]]

You can use <code>setTimeout</code> or <code>setInterval</code>.

The difference is - 
setTimeout triggers your function only once, and then you must set it again.
setInterval keeps triggering expression again and again, unless you tell it to stop

blocks|key|782072|text|可以，您可以使用JavaScript+setTimeout()方法或setInterval()方法来调用要运行的代码。下面是如何使用setTimeout来实现这一点：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|782073|function+executeQuery()+{
++$.ajax({
++++url:+'url/path/here',
++++success:+function(data)+{
++++++//+do+something+with+the+return+value+here+if+you+like
++++}
++});
++setTimeout(executeQuery,+5000);+//+you+could+choose+not+to+continue+on+failure...
}

$(document).ready(function()+{
++//+run+the+first+time;+all+subsequent+calls+will+take+care+of+themselves
++setTimeout(executeQuery,+5000);
});|code-block|syntax|javascript|782074|entityMap|0|LINK|mutability|MUTABLE|url|http://www.elated.com/articles/javascript-timers-with-settimeout-and-setinterval/^0|J|C|Y|D|J|C|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]]|D|@$9|X|A|Y|1|Z]]|E|$]]|$1|F|3|G|5|H|7|10|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|11|8|@]|D|@]|E|$]]]|L|$M|$5|N|O|P|E|$Q|R]]]]

Yes, you could use either the JavaScript <a href="http://www.elated.com/articles/javascript-timers-with-settimeout-and-setinterval/" rel="noreferrer"><code>setTimeout()</code></a> method or <code>setInterval()</code> method to invoke the code that you would like to run. Here's how you might do it with setTimeout:

<pre><code>function executeQuery() {
 $.ajax({
 url: 'url/path/here',
 success: function(data) {
 // do something with the return value here if you like
 }
 });
 setTimeout(executeQuery, 5000); // you could choose not to continue on failure...
}

$(document).ready(function() {
 // run the first time; all subsequent calls will take care of themselves
 setTimeout(executeQuery, 5000);
});
</code></pre>

blocks|key|996365|text|正如其他人指出的那样，setInterval和setTimeout将会做到这一点。我想强调一点更高级的技术，这是我从保罗·爱尔兰的这段优秀视频中学到的：http://paulirish.com/2010/10-things-i-learned-from-the-jquery-source/|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|996366|对于可能最终花费的时间超过重复间隔的周期性任务(如慢速连接上的HTTP请求)，最好不要使用setInterval()。如果第一个请求没有完成，而您启动了另一个请求，那么您可能会遇到多个请求消耗共享资源并彼此挨饿的情况。您可以通过等待调度下一个请求直到上一个请求完成来避免此问题：|style|CODE|996367|//+Use+a+named+immediately-invoked+function+expression.
(function+worker()+{
++$.get('ajax/test.html',+function(data)+{
++++//+Now+that+we've+completed+the+request+schedule+the+next+one.
++++$('.result').html(data);
++++setTimeout(worker,+5000);
++});
})();|code-block|syntax|javascript|996368|为了简单起见，我使用了success回调来进行调度。这样做的缺点是一个失败的请求将停止更新。为了避免这种情况，您可以使用完整的回调：|996369|(function+worker()+{
++$.ajax({
++++url:+'ajax/test.html',+
++++success:+function(data)+{
++++++$('.result').html(data);
++++},
++++complete:+function()+{
++++++//+Schedule+the+next+request+when+the+current+one's+complete
++++++setTimeout(worker,+5000);
++++}
++});
})();|996370|entityMap|0|LINK|mutability|MUTABLE|url|http://paulirish.com/2010/10-things-i-learned-from-the-jquery-source/^0|24|1X|0|0|19|D|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@]|9|@$A|Z|B|10|1|11]]|C|$]]|$1|D|3|E|5|6|7|12|8|@$A|13|B|14|F|G]]|9|@]|C|$]]|$1|H|3|I|5|J|7|15|8|@]|9|@]|C|$K|L]]|$1|M|3|N|5|6|7|16|8|@]|9|@]|C|$]]|$1|O|3|P|5|J|7|17|8|@]|9|@]|C|$K|L]]|$1|Q|3|-4|5|6|7|18|8|@]|9|@]|C|$]]]|R|$S|$5|T|U|V|C|$W|X]]]]

As others have pointed out setInterval and setTimeout will do the trick. I wanted to highlight a bit more advanced technique that I learned from this excellent video by Paul Irish: <a href="http://paulirish.com/2010/10-things-i-learned-from-the-jquery-source/" rel="noreferrer">http://paulirish.com/2010/10-things-i-learned-from-the-jquery-source/</a>

For periodic tasks that might end up taking longer than the repeat interval (like an HTTP request on a slow connection) it's best not to use <code>setInterval()</code>. If the first request hasn't completed and you start another one, you could end up in a situation where you have multiple requests that consume shared resources and starve each other. You can avoid this problem by waiting to schedule the next request until the last one has completed:

<pre><code>// Use a named immediately-invoked function expression.
(function worker() {
 $.get('ajax/test.html', function(data) {
 // Now that we've completed the request schedule the next one.
 $('.result').html(data);
 setTimeout(worker, 5000);
 });
})();
</code></pre>

For simplicity I used the success callback for scheduling. The down side of this is one failed request will stop updates. To avoid this you could use the complete callback instead:

<pre><code>(function worker() {
 $.ajax({
 url: 'ajax/test.html', 
 success: function(data) {
 $('.result').html(data);
 },
 complete: function() {
 // Schedule the next request when the current one's complete
 setTimeout(worker, 5000);
 }
 });
})();
</code></pre>

blocks|key|996394|text|我尝试了下面的代码，|type|unstyled|depth|inlineStyleRanges|entityRanges|data|996395|++++function+executeQuery()+{
++$.ajax({
++++url:+'url/path/here',
++++success:+function(data)+{
++++++//+do+something+with+the+return+value+here+if+you+like
++++}
++});
++setTimeout(executeQuery,+5000);+//+you+could+choose+not+to+continue+on+failure...
}

$(document).ready(function()+{
++//+run+the+first+time;+all+subsequent+calls+will+take+care+of+themselves
++setTimeout(executeQuery,+5000);
});|code-block|syntax|javascript|996396|这在指定的时间间隔内没有按预期工作，页面没有完全加载，函数被连续调用。最好在executeQuery()之外的一个单独函数中调用setTimeout(executeQuery,+5000);，如下所示。|offset|length|style|CODE|996397|function+executeQuery()+{
++$.ajax({
++++url:+'url/path/here',
++++success:+function(data)+{
++++++//+do+something+with+the+return+value+here+if+you+like
++++}
++});
++updateCall();
}

function+updateCall(){
setTimeout(function(){executeQuery()},+5000);
}

$(document).ready(function()+{
++executeQuery();
});|996398|这完全达到了预期的效果。|996399|entityMap^0|0|0|12|E|1S|V|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|U|8|@$I|V|J|W|K|L]|$I|X|J|Y|K|L]]|9|@]|A|$]]|$1|M|3|N|5|D|7|Z|8|@]|9|@]|A|$E|F]]|$1|O|3|P|5|6|7|10|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|11|8|@]|9|@]|A|$]]]|R|$]]

I tried the below code,

<pre><code> function executeQuery() {
 $.ajax({
 url: 'url/path/here',
 success: function(data) {
 // do something with the return value here if you like
 }
 });
 setTimeout(executeQuery, 5000); // you could choose not to continue on failure...
}

$(document).ready(function() {
 // run the first time; all subsequent calls will take care of themselves
 setTimeout(executeQuery, 5000);
});
</code></pre>

This didn't work as expected for the specified interval,the page didn't load completely and the function was been called continuously.
Its better to call <code>setTimeout(executeQuery, 5000);</code> outside <code>executeQuery()</code> in a separate function as below,

<pre><code>function executeQuery() {
 $.ajax({
 url: 'url/path/here',
 success: function(data) {
 // do something with the return value here if you like
 }
 });
 updateCall();
}

function updateCall(){
setTimeout(function(){executeQuery()}, 5000);
}

$(document).ready(function() {
 executeQuery();
});
</code></pre>

This worked exactly as intended.

<pre><code>&lt;meta http-equiv="Refresh" Content="5"&gt;
</code></pre>

This script reloads or refresh the page after every 5 seconds. But I want to do it using jQuery and AJAX call. Is it possible?

How to fire AJAX request Periodically?

jQuery

问如何定期触发AJAX请求？
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