blocks|key|4137866|text|这个循环肯定比你所拥有的更简洁，但是在不同的浏览器中运行一些测试来找出哪个更快是值得的。我认为正则表达式匹配可能更快，但我很好奇编译正则表达式是否会有任何性能损失。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4137867|for(var+i=0;+i<aValidWords.length;+i%2B%2B)+{
++++if+(new+RegExp(aValidWords[i],+'i').test(sMainWord))
++++++++aPossibleWords.push(aValidWords[i]);
}|code-block|syntax|javascript|4137868|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

This loop is definitely more concise than what you have, but it'd be worth running some tests in various browsers to find out which is faster. I imagine Regex matching is probably faster, but I'm curious whether there's any performance penalty for compiling the Regex.

<pre><code>for(var i=0; i&lt;aValidWords.length; i++) {
 if (new RegExp(aValidWords[i], 'i').test(sMainWord))
 aPossibleWords.push(aValidWords[i]);
}
</code></pre>

blocks|key|788089|text|我比较了三种可能的实现：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|788090|Alternative+1+-使用for循环：|offset|length|style|BOLD|788091|function+alternative1(aValidWords,+sMainWordLower)+{
++++var+aPossibleWords1+=+[];
++++for(i=0;+i+<+aValidWords.length;+i%2B%2B){
++++++++if(sMainWordLower.indexOf(aValidWords[i])+!=+-1){
++++++++++++aPossibleWords1.push(aValidWords[i]);
++++++++}
++++}
++++return+aPossibleWords1;
}|code-block|syntax|javascript|788092|Alternative+2+-使用jQuery+grep函数：|788093|function+alternative2(aValidWords,+sMainWordLower)+{
++++return+$.grep(aValidWords,+function(word)+{
++++++++++++++return+sMainWordLower.indexOf(word)+!=+-1;++++++++++++++++++++
+++++++++}
++++)
}|788094|Alternative+3+-使用JavaScript原生filter方法(IE9、Chrome、Firefox、Opera、Safari)：|788095|function+alternative3(aValidWords,+sMainWordLower)+{
++++return+aValidWords.filter(function(word)+{
++++++++++++++return+sMainWordLower.indexOf(word)+!=+-1;++++++++++++++++++++
+++++++++}
++++)
}|788096|我用Chrome+Profile工具测量了执行时间。每种选择被执行10次，并使用随机的milion字数组。结果是：|788097|788098|Alternative+1+21,68s|unordered-list-item|788099|Alternative+:+20+executions++->+21，68s|788100|Alternative+2：20+executions+->+21，68s|788101|Alternative+3+->：20+executions+->+34,66s|788102|788103|令我惊讶的是，原生JavaScript+Filter函数速度如此之慢。|788104|如果您不想自己测量执行时间，可以使用jsFiddle+-它需要一些时间才能完成脚本。|788105|一般来说，这三种选择是最简单的。如果这些执行时间适合您，请使用其中之一，否则@Pumbaa80的答案是正确的。|788106|更新|788107|有关结果的解释(为什么JQuery+grep函数比原生JavaScript过滤器函数更快)，请查看此question/answer。多亏了@Alexander，jsFiddle代码也被移植到了jsPerf上。|788108|entityMap|0|LINK|mutability|MUTABLE|url|http://api.jquery.com/jQuery.grep/|1|2|https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Array/filter|3|http://jsfiddle.net/hfhRC/18/|4|https://stackoverflow.com/q/14091065/617996|5|6|http://jsperf.com/filterings^0|0|0|D|0|0|0|D|O|4|0|0|0|0|D|T|6|1|0|0|0|0|0|K|0|0|12|0|0|11|0|0|14|0|0|0|Z|K|6|2|0|0|16|I|8|3|0|0|1J|0|0|2|0|0|2W|1E|F|4|28|8|5|2O|6|6|0^^$0|@$1|2|3|4|5|6|7|1Z|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|20|8|@$D|21|E|22|F|G]]|9|@]|A|$]]|$1|H|3|I|5|J|7|23|8|@]|9|@]|A|$K|L]]|$1|M|3|N|5|6|7|24|8|@$D|25|E|26|F|G]]|9|@$D|27|E|28|1|29]]|A|$]]|$1|O|3|P|5|J|7|2A|8|@]|9|@]|A|$K|L]]|$1|Q|3|R|5|6|7|2B|8|@$D|2C|E|2D|F|G]]|9|@$D|2E|E|2F|1|2G]]|A|$]]|$1|S|3|T|5|J|7|2H|8|@]|9|@]|A|$K|L]]|$1|U|3|V|5|6|7|2I|8|@]|9|@]|A|$]]|$1|W|3|-4|5|6|7|2J|8|@]|9|@]|A|$]]|$1|X|3|Y|5|Z|7|2K|8|@$D|2L|E|2M|F|G]]|9|@]|A|$]]|$1|10|3|11|5|Z|7|2N|8|@$D|2O|E|2P|F|G]]|9|@]|A|$]]|$1|12|3|13|5|Z|7|2Q|8|@$D|2R|E|2S|F|G]]|9|@]|A|$]]|$1|14|3|15|5|Z|7|2T|8|@$D|2U|E|2V|F|G]]|9|@]|A|$]]|$1|16|3|-4|5|6|7|2W|8|@]|9|@]|A|$]]|$1|17|3|18|5|6|7|2X|8|@$D|2Y|E|2Z|F|G]]|9|@$D|30|E|31|1|32]]|A|$]]|$1|19|3|1A|5|6|7|33|8|@$D|34|E|35|F|G]]|9|@$D|36|E|37|1|38]]|A|$]]|$1|1B|3|1C|5|6|7|39|8|@$D|3A|E|3B|F|G]]|9|@]|A|$]]|$1|1D|3|1E|5|6|7|3C|8|@$D|3D|E|3E|F|G]]|9|@]|A|$]]|$1|1F|3|1G|5|6|7|3F|8|@$D|3G|E|3H|F|G]]|9|@$D|3I|E|3J|1|3K]|$D|3L|E|3M|1|3N]|$D|3O|E|3P|1|3Q]]|A|$]]|$1|1H|3|-4|5|6|7|3R|8|@]|9|@]|A|$]]]|1I|$1J|$5|1K|1L|1M|A|$1N|1O]]|1P|$5|1K|1L|1M|A|$1N|1O]]|1Q|$5|1K|1L|1M|A|$1N|1R]]|1S|$5|1K|1L|1M|A|$1N|1T]]|1U|$5|1K|1L|1M|A|$1N|1V]]|1W|$5|1K|1L|1M|A|$1N|1T]]|1X|$5|1K|1L|1M|A|$1N|1Y]]]]

I compared three possible implementations:

Alternative 1 - Using for loop:

<pre><code>function alternative1(aValidWords, sMainWordLower) {
 var aPossibleWords1 = [];
 for(i=0; i &lt; aValidWords.length; i++){
 if(sMainWordLower.indexOf(aValidWords[i]) != -1){
 aPossibleWords1.push(aValidWords[i]);
 }
 }
 return aPossibleWords1;
}
</code></pre>

Alternative 2 - Using jQuery <a href="http://api.jquery.com/jQuery.grep/" rel="nofollow noreferrer">grep</a> function:

<pre><code>function alternative2(aValidWords, sMainWordLower) {
 return $.grep(aValidWords, function(word) {
 return sMainWordLower.indexOf(word) != -1; 
 }
 )
}
</code></pre>

Alternative 3 - Using JavaScript native <a href="http://api.jquery.com/jQuery.grep/" rel="nofollow noreferrer">filter</a> method (IE9, Chrome, Firefox, Opera, Safari):

<pre><code>function alternative3(aValidWords, sMainWordLower) {
 return aValidWords.filter(function(word) {
 return sMainWordLower.indexOf(word) != -1; 
 }
 )
}
</code></pre>

I measured the execution times with Chrome Profile tool. Each alternative was executed 10 times with array of random milion words. The results are:

<ul>
<li>Alternative 1: 20 executions -> 21,68s</li>
<li>Alternative 2: 20 executions -> 26,31s</li>
<li>Alternative 3: 20 executions -> 34,66s</li>
</ul>

I was surprised by the fact, that native JavaScript <a href="https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Global_Objects/Array/filter" rel="nofollow noreferrer">Filter</a> function was so slow. 

If you wan't to measure execution times by yourself, there is <a href="http://jsfiddle.net/hfhRC/18/" rel="nofollow noreferrer">jsFiddle</a> - it will take some time for script to finish.

In general those three alternatives are easiest. If those execution times suits you, use one of them, otherwise the answer of @Pumbaa80 is the right one.

<h2>[UPDATE]</h2>

For the explanation of the results (why JQuery grep funcion is faster then native JavaScript filter function) please take a look at this <a href="https://stackoverflow.com/q/14091065/617996">question/answer</a>.
<a href="http://jsfiddle.net/hfhRC/18/" rel="nofollow noreferrer">jsFiddle</a> code was also ported to <a href="http://jsperf.com/filterings" rel="nofollow noreferrer">jsPerf</a> thanks to @Alexander.

blocks|key|4620534|text|我认为你的代码是不错的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4620535|如果你真的很担心性能，你可能想尝试一些复杂的方法，比如Boyer-Moore。但是，如果您只有几个模式和相对较短的字符串，那么初始化开销将高于收益，因此您应该坚持使用简单的方法。请参阅维基百科的比较表http://en.wikipedia.org/wiki/String_searching_algorithm#Single_pattern_algorithms|offset|length|4620536|entityMap|0|LINK|mutability|MUTABLE|url|http://en.wikipedia.org/wiki/Boyer%25E2%2580%2593Moore_string_search_algorithm|1|http://en.wikipedia.org/wiki/String_searching_algorithm#Single_pattern_algorithms^0|0|R|B|0|2S|29|1|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Q|8|@]|9|@$D|R|E|S|1|T]|$D|U|E|V|1|W]]|A|$]]|$1|F|3|-4|5|6|7|X|8|@]|9|@]|A|$]]]|G|$H|$5|I|J|K|A|$L|M]]|N|$5|I|J|K|A|$L|O]]]]

I think your code is decent.

If you're really worried about performance, you may want to try some sophisticated method like <a href="http://en.wikipedia.org/wiki/Boyer%E2%80%93Moore_string_search_algorithm" rel="nofollow">Boyer-Moore</a>.
But, if you just have a handful of patterns and relatively short strings, then the initialization overhead is higher than the benefit, so you should stick with the simple approach. See Wikipedia's comparison table <a href="http://en.wikipedia.org/wiki/String_searching_algorithm#Single_pattern_algorithms" rel="nofollow">http://en.wikipedia.org/wiki/String_searching_algorithm#Single_pattern_algorithms</a>

Basically, I need to get the words from the array which are contained in the main string

I have a looping code here but I think there is a one-liner to do the trick.
I need the code to be optimized not only in code length but also in performance.

Thanks

<pre><code>var aValidWords = ["ex", "exes", "expert", 
 "experts", "expertise", "sex", "sexes", 
 "exchange", "change", "changes"];
var sMainWord = "expertsExchange";
var aPossibleWords = new Array();

var sMainWordLower = sMainWord.toLowerCase();
for(i=0; i &lt; aValidWords.length; i++){
 var sCurrentWord = aValidWords[i].toLowerCase();
 if(sMainWordLower.indexOf(sCurrentWord) != -1){
 aPossibleWords.push(aValidWords[i]);
 }
}

document.write(aPossibleWords.join("&lt;br /&gt;"));
</code></pre>

Optimize javascript code on searching for matches in array

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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基本上，我需要从包含在主字符串中的数组中获取单词我这里有一个循环代码，但我认为有一个一行程序可以做到这一点。我需要的代码被优化，不仅在代码长度，而且在性能。谢谢var aValidWords = ["ex", "exes", "expert",                    "experts", "expert...

问在数组中搜索匹配项时优化javascript代码
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