blocks|key|906914|text|var+index+=+items.indexOf(3452);

if+(index+!==+-1)+{
++++items[index]+=+1010;
}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|906915|另外，建议您不要使用构造函数方法来初始化数组。相反，请使用文字语法：|unstyled|906916|var+items+=+[523,+3452,+334,+31,+5346];|906917|如果您正在使用简明的JavaScript并希望缩短-1比较，也可以使用~运算符：|offset|length|style|CODE|906918|var+index+=+items.indexOf(3452);

if+(~index)+{
++++items[index]+=+1010;
}|906919|有时我甚至喜欢写一个contains函数来抽象化这个检查，让它更容易理解发生了什么。令人敬畏的是，它同时适用于数组和字符串：|906920|var+contains+=+function+(haystack,+needle)+{
++++return+!!~haystack.indexOf(needle);
};

//+can+be+used+like+so+now:
if+(contains(items,+3452))+{
++++//+do+something+else...
}|906921|从用于字符串的ES6/ES2015开始，以及建议用于数组的ES2016，您可以更轻松地确定源是否包含其他值：|906922|if+(haystack.includes(needle))+{
++++//+do+your+thing
}|906923|entityMap^0|0|0|0|P|2|Z|1|0|0|A|8|0|0|0|0^^$0|@$1|2|3|4|5|6|7|10|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|11|8|@]|9|@]|A|$]]|$1|G|3|H|5|6|7|12|8|@]|9|@]|A|$B|C]]|$1|I|3|J|5|F|7|13|8|@$K|14|L|15|M|N]|$K|16|L|17|M|N]]|9|@]|A|$]]|$1|O|3|P|5|6|7|18|8|@]|9|@]|A|$B|C]]|$1|Q|3|R|5|F|7|19|8|@$K|1A|L|1B|M|N]]|9|@]|A|$]]|$1|S|3|T|5|6|7|1C|8|@]|9|@]|A|$B|C]]|$1|U|3|V|5|F|7|1D|8|@]|9|@]|A|$]]|$1|W|3|X|5|6|7|1E|8|@]|9|@]|A|$B|C]]|$1|Y|3|-4|5|F|7|1F|8|@]|9|@]|A|$]]]|Z|$]]

<pre><code>var index = items.indexOf(3452);

if (index !== -1) {
    items[index] = 1010;
}
</code></pre>

<p>Also it is recommend you not use the constructor method to initialize your arrays. Instead, use the literal syntax:</p>

<pre><code>var items = [523, 3452, 334, 31, 5346];
</code></pre>

<p>You can also use the <code>~</code> operator if you are into terse JavaScript and want to shorten the <code>-1</code> comparison:</p>

<pre><code>var index = items.indexOf(3452);

if (~index) {
    items[index] = 1010;
}
</code></pre>

<p>Sometimes I even like to write a <code>contains</code> function to abstract this check and make it easier to understand what's going on. What's awesome is this works on arrays and strings both:</p>

<pre><code>var contains = function (haystack, needle) {
    return !!~haystack.indexOf(needle);
};

// can be used like so now:
if (contains(items, 3452)) {
    // do something else...
}
</code></pre>

<p>Starting with ES6/ES2015 for strings, and proposed for ES2016 for arrays, you can more easily determine if a source contains another value:</p>

<pre><code>if (haystack.includes(needle)) {
    // do your thing
}
</code></pre>


blocks|key|690752|text|Array.indexOf()方法将替换第一个实例。要获取每个实例，请使用Array.map()|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|690753|a+=+a.map(function(item)+{+return+item+==+3452+?+1010+:+item;+});|code-block|syntax|javascript|690754|当然，这会创建一个新的数组。如果您想就地执行此操作，请使用Array.forEach()|690755|a.forEach(function(item,+i)+{+if+(item+==+3452)+a[i]+=+1010;+});|690756|entityMap^0|0|F|11|B|0|0|T|F|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]|$9|T|A|U|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|M|3|N|5|H|7|Z|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|10|8|@]|D|@]|E|$]]]|P|$]]

<p>The <code>Array.indexOf()</code> method will replace the first instance.  To get every instance use <code>Array.map()</code>:</p>

<pre><code>a = a.map(function(item) { return item == 3452 ? 1010 : item; });
</code></pre>

<p>Of course, that creates a new array.  If you want to do it in place, use <code>Array.forEach()</code>:</p>

<pre><code>a.forEach(function(item, i) { if (item == 3452) a[i] = 1010; });
</code></pre>


blocks|key|690977|text|我建议的解决方案是：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|690978|items.splice(1,+1,+1010);|code-block|syntax|javascript|690979|拼接操作将从数组中位置1开始删除1个项(即3452)，并用新的项1010替换它。|offset|length|style|CODE|690980|entityMap^0|0|0|L|4|W|4|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]|$I|T|J|U|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|V|8|@]|9|@]|A|$]]]|N|$]]

<p>My suggested solution would be:</p>

<pre><code>items.splice(1, 1, 1010);
</code></pre>

<p>The splice operation will remove 1 item, starting at position 1 in the array (i.e. <code>3452</code>), and will replace it with the new item <code>1010</code>.</p>


blocks|key|906794|text|使用indexOf查找元素。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|906795|var+i+=+items.indexOf(3452);
items[i]+=+1010;|code-block|syntax|javascript|906796|entityMap^0|2|7|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

<p>Use <code>indexOf</code> to find an element.</p>
<pre><code>var i = items.indexOf(3452);
items[i] = 1010;
</code></pre>


blocks|key|906751|text|使用for循环可以轻松完成。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|906752|for+(var+i+=+0;+i+<+items.length;+i%2B%2B)
++++if+(items[i]+==+3452)
++++++++items[i]+=+1010;|code-block|syntax|javascript|906753|entityMap^0|2|3|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

<p>Easily accomplished with a <code>for</code> loop.</p>

<pre><code>for (var i = 0; i &lt; items.length; i++)
    if (items[i] == 3452)
        items[i] = 1010;
</code></pre>


blocks|key|691410|text|第一种方法|type|unstyled|depth|inlineStyleRanges|entityRanges|data|691411|在一行中替换或更新数组项的最佳方式|691412|array.splice(array.indexOf(valueToReplace),+1,+newValue)|code-block|syntax|javascript|691413|例如：|691414|let+items+=+['JS',+'PHP',+'RUBY'];

let+replacedItem+=+items.splice(items.indexOf('RUBY'),+1,+'PYTHON')

console.log(replacedItem)+//['RUBY']
console.log(items)+//['JS',+'PHP',+'PYTHON']|691415|第二种方法|691416|执行相同操作的另一种简单方法是：|691417|items[items.indexOf(oldValue)]+=+newValue|691418|entityMap^0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|W|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|X|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|Y|8|@]|9|@]|A|$G|H]]|$1|M|3|N|5|6|7|Z|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|10|8|@]|9|@]|A|$]]|$1|Q|3|R|5|F|7|11|8|@]|9|@]|A|$G|H]]|$1|S|3|-4|5|6|7|12|8|@]|9|@]|A|$]]]|T|$]]

<h1>First method</h1>

<p>Best way in just one line to replace or update item of array</p>

<pre><code>array.splice(array.indexOf(valueToReplace), 1, newValue)
</code></pre>

<p>Eg: </p>

<pre><code>let items = ['JS', 'PHP', 'RUBY'];

let replacedItem = items.splice(items.indexOf('RUBY'), 1, 'PYTHON')

console.log(replacedItem) //['RUBY']
console.log(items) //['JS', 'PHP', 'PYTHON']
</code></pre>

<h1>Second method</h1>

<p>An other simple way to do the same operation is :</p>

<pre><code>items[items.indexOf(oldValue)] = newValue
</code></pre>


blocks|key|691152|text|如果使用复杂的对象(或者甚至是简单的对象)，并且可以使用es6，那么Array.prototype.findIndex就是一个很好的选择。对于行动的数组，他们可以做到，|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|691153|const+index+=+items.findIndex(x+=>+x+===+3452)
items[index]+=+1010|code-block|syntax|javascript|691154|对于更复杂的对象，这真的很棒。例如,|691155|const+index+=+
++++items.findIndex(
+++++++x+=>+x.jerseyNumber+===+9+&&+x.school+===+'Ohio+State'
++++)

items[index].lastName+=+'Utah'
items[index].firstName+=+'Johnny'|691156|entityMap^0|Y|P|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|P|$]]

<p>If using a complex object (or even a simple one) and you can use es6, <code>Array.prototype.findIndex</code> is a good one. For the OP's array, they could do, </p>

<pre><code>const index = items.findIndex(x =&gt; x === 3452)
items[index] = 1010
</code></pre>

<p>For more complex objects, this really shines. For example, </p>

<pre><code>const index = 
    items.findIndex(
       x =&gt; x.jerseyNumber === 9 &amp;&amp; x.school === 'Ohio State'
    )

items[index].lastName = 'Utah'
items[index].firstName = 'Johnny'
</code></pre>


blocks|key|690609|text|您可以使用索引编辑任意数量的列表|type|unstyled|depth|inlineStyleRanges|entityRanges|data|690610|例如：|690611|items[0]+=+5;
items[5]+=+100;|code-block|syntax|javascript|690612|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|L|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|M|8|@]|9|@]|A|$G|H]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

<p>You can edit any number of the list using indexes</p>

<p>for example : </p>

<pre><code>items[0] = 5;
items[5] = 100;
</code></pre>


blocks|key|907963|text|在javascript中替换数组元素的函数式方法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|907964|​|907965|const+replace+=+(array,+index,+...items)+=>+[...array.slice(0,+index),+...items,+...array.slice(index+%2B+1)];|code-block|syntax|javascript|907966|907967|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|M|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|N|8|@]|9|@]|A|$G|H]]|$1|I|3|C|5|6|7|O|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|P|8|@]|9|@]|A|$]]]|K|$]]

<p>A functional approach to replacing an element of an array in javascript:</p>
<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>const replace = (array, index, ...items) =&gt; [...array.slice(0, index), ...items, ...array.slice(index + 1)];</code></pre>
</div>
</div>
</p>


blocks|key|907346|text|替换可以在一行代码中完成：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|907347|​|907348|var+items+=+Array(523,+3452,+334,+31,+5346);

items[items.map((e,+i)+=>+[i,+e]).filter(e+=>+e[1]+==+3452)[0][0]]+=+1010

console.log(items);|code-block|syntax|javascript|907349|907350|或者创建一个要重用的函数：|907351|907352|Array.prototype.replace+=+function(t,+v)+{
++++if+(this.indexOf(t)!=+-1)
++++++++this[this.map((e,+i)+=>+[i,+e]).filter(e+=>+e[1]+==+t)[0][0]]+=+v;
++};

//Check
var+items+=+Array(523,+3452,+334,+31,+5346);
items.replace(3452,+1010);
console.log(items);|907353|907354|entityMap^0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|S|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|T|8|@]|9|@]|A|$G|H]]|$1|I|3|C|5|6|7|U|8|@]|9|@]|A|$]]|$1|J|3|K|5|6|7|V|8|@]|9|@]|A|$]]|$1|L|3|C|5|6|7|W|8|@]|9|@]|A|$]]|$1|M|3|N|5|F|7|X|8|@]|9|@]|A|$G|H]]|$1|O|3|C|5|6|7|Y|8|@]|9|@]|A|$]]|$1|P|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]]|Q|$]]

<p>Replacement can be done in one line:</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>var items = Array(523, 3452, 334, 31, 5346);

items[items.map((e, i) =&gt; [i, e]).filter(e =&gt; e[1] == 3452)[0][0]] = 1010

console.log(items);</code></pre>
</div>
</div>
</p>

<p>Or create a function to reuse:</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>Array.prototype.replace = function(t, v) {
    if (this.indexOf(t)!= -1)
        this[this.map((e, i) =&gt; [i, e]).filter(e =&gt; e[1] == t)[0][0]] = v;
  };

//Check
var items = Array(523, 3452, 334, 31, 5346);
items.replace(3452, 1010);
console.log(items);</code></pre>
</div>
</div>
</p>


blocks|key|907400|text|使用ES6扩散运算符和.slice方法替换列表中元素的不可变方法。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|907401|const+arr+=+['fir',+'next',+'third'],+item+=+'next'

const+nextArr+=+[
++...arr.slice(0,+arr.indexOf(item)),+
++'second',
++...arr.slice(arr.indexOf(item)+%2B+1)
]|code-block|syntax|javascript|907402|验证是否正常工作|907403|console.log(arr)+++++//+[+'fir',+'next',+'third'+]
console.log(nextArr)+//+['fir',+'second',+'third']|907404|entityMap^0|B|6|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@$9|R|A|S|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|T|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|U|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|V|8|@]|D|@]|E|$I|J]]|$1|O|3|-4|5|6|7|W|8|@]|D|@]|E|$]]]|P|$]]

<p>The immutable way to replace the element in the list using ES6 spread operators and <code>.slice</code> method.</p>

<pre><code>const arr = ['fir', 'next', 'third'], item = 'next'

const nextArr = [
  ...arr.slice(0, arr.indexOf(item)), 
  'second',
  ...arr.slice(arr.indexOf(item) + 1)
]
</code></pre>

<p>Verify that works</p>

<pre><code>console.log(arr)     // [ 'fir', 'next', 'third' ]
console.log(nextArr) // ['fir', 'second', 'third']
</code></pre>


blocks|key|907014|text|最简单的方法是使用一些库，如underscorejs和map+method。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|907015|var+items+=+Array(523,3452,334,31,...5346);

_.map(items,+function(num)+{
++return+(num+==+3452)+?+1010+:+num;+
});
=>+[523,+1010,+334,+31,+...5346]|code-block|syntax|javascript|907016|entityMap|0|LINK|mutability|MUTABLE|url|http://underscorejs.org/#map^0|E|C|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|F|7|U|8|@]|9|@]|C|$G|H]]|$1|I|3|-4|5|6|7|V|8|@]|9|@]|C|$]]]|J|$K|$5|L|M|N|C|$O|P]]]]

<p>The easiest way is to use some libraries like <a href="http://underscorejs.org/#map" rel="nofollow">underscorejs</a> and map method.</p>

<pre><code>var items = Array(523,3452,334,31,...5346);

_.map(items, function(num) {
  return (num == 3452) ? 1010 : num; 
});
=&gt; [523, 1010, 334, 31, ...5346]
</code></pre>


blocks|key|907069|text|var+items+=+Array(523,3452,334,31,5346);|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|907070|如果您知道该值，则使用，|unstyled|907071|items[items.indexOf(334)]+=+1010;|907072|如果您想知道值是否存在，那么可以使用，|907073|var+point+=+items.indexOf(334);

if+(point+!==+-1)+{
++++items[point]+=+1010;
}|907074|如果你知道地点(位置)，那么直接使用，|907075|items[--position]+=+1010;|907076|如果你想替换几个元素，并且你知道只有起始位置只意味着，|907077|items.splice(2,+1,+1010,+1220);|907078|有关.splice的更多信息|offset|length|907079|entityMap|0|LINK|mutability|MUTABLE|url|http://www.w3schools.com/jsref/jsref_splice.asp^0|0|0|0|0|0|0|0|0|0|2|7|0|0^^$0|@$1|2|3|4|5|6|7|16|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|17|8|@]|9|@]|A|$]]|$1|G|3|H|5|6|7|18|8|@]|9|@]|A|$B|C]]|$1|I|3|J|5|F|7|19|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|1A|8|@]|9|@]|A|$B|C]]|$1|M|3|N|5|F|7|1B|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|1C|8|@]|9|@]|A|$B|C]]|$1|Q|3|R|5|F|7|1D|8|@]|9|@]|A|$]]|$1|S|3|T|5|6|7|1E|8|@]|9|@]|A|$B|C]]|$1|U|3|V|5|F|7|1F|8|@]|9|@$W|1G|X|1H|1|1I]]|A|$]]|$1|Y|3|-4|5|F|7|1J|8|@]|9|@]|A|$]]]|Z|$10|$5|11|12|13|A|$14|15]]]]

<pre><code>var items = Array(523,3452,334,31,5346);
</code></pre>

<p>If you know the value then use,</p>

<pre><code>items[items.indexOf(334)] = 1010;
</code></pre>

<p>If you want to know that value is present or not, then use,</p>

<pre><code>var point = items.indexOf(334);

if (point !== -1) {
    items[point] = 1010;
}
</code></pre>

<p>If you know the place (position) then directly use,</p>

<pre><code>items[--position] = 1010;
</code></pre>

<p>If you want replace few elements, and you know only starting position only means,</p>

<pre><code>items.splice(2, 1, 1010, 1220);
</code></pre>

<p>for more about <a href="http://www.w3schools.com/jsref/jsref_splice.asp" rel="nofollow">.splice</a></p>


blocks|key|691483|text|如果有人对如何从数组中的索引替换对象感兴趣，这里有一个解决方案。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|691484|根据id查找对象的索引：|691485|const+index+=+items.map(item+=>+item.id).indexOf(objectId)|code-block|syntax|javascript|691486|使用Object.assign()方法替换对象：|691487|Object.assign(items[index],+newValue)|691488|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Q|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|S|8|@]|9|@]|A|$G|H]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

<p>Well if anyone is interresting on how to replace an object from its index in an array, here's a solution.</p>

<p>Find the index of the object by its id:</p>

<pre><code>const index = items.map(item =&gt; item.id).indexOf(objectId)
</code></pre>

<p>Replace the object using Object.assign() method:</p>

<pre><code>Object.assign(items[index], newValue)
</code></pre>


blocks|key|907848|text|如果你想要一个简单的白糖sintax眼线笔，你可以：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|907849|(elements+=+elements.filter(element+=>+element.id+!==+updatedElement.id)).push(updatedElement);|code-block|syntax|javascript|907850|像这样：|907851|let+elements+=+[+{+id:+1,+name:+'element+one'+},+{+id:+2,+name:+'element+two'}+];
const+updatedElement+=+{+id:+1,+name:+'updated+element+one'+};|907852|如果你没有id，你可以像下面这样串化元素：|907853|(elements+=+elements.filter(element+=>+JSON.stringify(element)+!==+JSON.stringify(updatedElement))).push(updatedElement);|907854|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|D|7|V|8|@]|9|@]|A|$E|F]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

<p>If you want a simple sugar sintax oneliner you can just:</p>

<pre><code>(elements = elements.filter(element =&gt; element.id !== updatedElement.id)).push(updatedElement);
</code></pre>

<p>Like:</p>

<pre><code>let elements = [ { id: 1, name: 'element one' }, { id: 2, name: 'element two'} ];
const updatedElement = { id: 1, name: 'updated element one' };
</code></pre>

<p>If you don't have id you could stringify the element like:</p>

<pre><code>(elements = elements.filter(element =&gt; JSON.stringify(element) !== JSON.stringify(updatedElement))).push(updatedElement);
</code></pre>


blocks|key|690936|text|下面是一个可重用函数的基本答案：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|690937|function+arrayFindReplace(array,+findValue,+replaceValue){
++++while(array.indexOf(findValue)+!==+-1){
++++++++let+index+=+array.indexOf(findValue);
++++++++array[index]+=+replaceValue;
++++}
}|code-block|syntax|javascript|690938|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|$]]

<p>Here is the basic answer made into a reusable function:</p>

<pre><code>function arrayFindReplace(array, findValue, replaceValue){
    while(array.indexOf(findValue) !== -1){
        let index = array.indexOf(findValue);
        array[index] = replaceValue;
    }
}
</code></pre>


blocks|key|691319|text|var+index+=+Array.indexOf(Array+value);
++++++++if+(index+>+-1)+{
++++++++++Array.splice(index,+1);
++++++++}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|691320|在这里，您可以从数组中删除一个特定值，并根据相同的索引在数组中插入值。|unstyled|691321|+Array.splice(index,+0,+Array+value);|691322|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|L|8|@]|9|@]|A|$]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$B|C]]|$1|I|3|-4|5|F|7|N|8|@]|9|@]|A|$]]]|J|$]]

<pre><code>var index = Array.indexOf(Array value);
        if (index &gt; -1) {
          Array.splice(index, 1);
        }
</code></pre>

<p>from here you can delete a particular value from array and based on the same index 
 you can insert value in array .</p>

<pre><code> Array.splice(index, 0, Array value);
</code></pre>


blocks|key|691767|text|这是一条直线。它假定该项将在数组中。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|691768|​|691769|var+items+=+[523,+3452,+334,+31,+5346]
var+replace+=+(arr,+oldVal,+newVal)+=>+(arr[arr.indexOf(oldVal)]+=+newVal,+arr)
console.log(replace(items,+3452,+1010))|code-block|syntax|javascript|691770|691771|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|M|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|N|8|@]|9|@]|A|$G|H]]|$1|I|3|C|5|6|7|O|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|P|8|@]|9|@]|A|$]]]|K|$]]

<p>Here's a one liner. It assumes the item will be in the array.</p>

<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>var items = [523, 3452, 334, 31, 5346]
var replace = (arr, oldVal, newVal) =&gt; (arr[arr.indexOf(oldVal)] = newVal, arr)
console.log(replace(items, 3452, 1010))</code></pre>
</div>
</div>
</p>


blocks|key|907871|text|+items[items.indexOf(3452)]+=+1010|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|907872|非常适合简单的交换。试试下面的代码片段|unstyled|907873|​|907874|const+items+=+Array(523,+3452,+334,+31,+5346);
console.log(items)

items[items.indexOf(3452)]+=+1010
console.log(items)|907875|907876|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|O|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|P|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|Q|8|@]|9|@]|A|$B|C]]|$1|K|3|H|5|F|7|R|8|@]|9|@]|A|$]]|$1|L|3|-4|5|F|7|S|8|@]|9|@]|A|$]]]|M|$]]

<pre><code> items[items.indexOf(3452)] = 1010
</code></pre>
<p>great for simple swaps. try the snippet below</p>
<p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
<div class="snippet-code">
<pre class="snippet-code-js lang-js prettyprint-override"><code>const items = Array(523, 3452, 334, 31, 5346);
console.log(items)

items[items.indexOf(3452)] = 1010
console.log(items)</code></pre>
</div>
</div>
</p>


blocks|key|690897|text|首先，像这样重写你的数组：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|690898|var+items+=+[523,3452,334,31,...5346];|code-block|syntax|javascript|690899|接下来，通过元素的索引号访问数组中的元素。确定索引号的公式是：n-1|offset|length|style|CODE|690900|要替换数组中的第一项(n=1)，请编写：|690901|items[0]+=+Enter+Your+New+Number;|690902|在您的示例中，数字3452位于第二个位置(n=2)。因此，确定索引号的公式是2-1+=+1。因此，请编写以下代码，用1010替换3452|690903|items[1]+=+1010;|690904|entityMap^0|0|0|V|3|0|A|5|0|0|9|4|K|5|12|7|1M|4|1S|4|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|X|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Y|8|@$I|Z|J|10|K|L]]|9|@]|A|$]]|$1|M|3|N|5|6|7|11|8|@$I|12|J|13|K|L]]|9|@]|A|$]]|$1|O|3|P|5|D|7|14|8|@]|9|@]|A|$E|F]]|$1|Q|3|R|5|6|7|15|8|@$I|16|J|17|K|L]|$I|18|J|19|K|L]|$I|1A|J|1B|K|L]|$I|1C|J|1D|K|L]|$I|1E|J|1F|K|L]]|9|@]|A|$]]|$1|S|3|T|5|D|7|1G|8|@]|9|@]|A|$E|F]]|$1|U|3|-4|5|6|7|1H|8|@]|9|@]|A|$]]]|V|$]]

<p>First, rewrite your array like this: </p>

<pre><code>var items = [523,3452,334,31,...5346];
</code></pre>

<p>Next, access the element in the array through its index number. The formula to determine the index number is: <code>n-1</code></p>

<p>To replace the first item <code>(n=1)</code> in the array, write:</p>

<pre><code>items[0] = Enter Your New Number;
</code></pre>

<p>In your example, the number <code>3452</code> is in the second position <code>(n=2)</code>. So the formula to determine the index number is <code>2-1 = 1</code>. So write the following code to replace <code>3452</code> with <code>1010</code>:</p>

<pre><code>items[1] = 1010;
</code></pre>


blocks|key|691079|text|我解决了这个问题，使用for循环，迭代通过原始数组，将匹配work的位置添加到另一个数组中，然后循环通过该数组，在原始数组中更改它，然后返回它。我使用和箭头函数，但常规函数也可以。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|691080|var+replace+=+(arr,+replaceThis,+WithThis)+=>+{
++++if+(!Array.isArray(arr))+throw+new+RangeError("Error");
++++var+itemSpots+=+[];
++++for+(var+i+=+0;+i+<+arr.length;+i%2B%2B)+{
++++++++if+(arr[i]+==+replaceThis)+itemSpots.push(i);
++++}

++++for+(var+i+=+0;+i+<+itemSpots.length;+i%2B%2B)+{
++++++++arr[itemSpots[i]]+=+WithThis;
++++}

++++return+arr;
};|code-block|syntax|javascript|691081|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|$]]

<p>I solved this problem using for loops and iterating through the original array and adding the positions of the matching arreas to another array and then looping through that array and changing it in the original array then return it, I used and arrow function but a regular function would work too.</p>

<pre><code>var replace = (arr, replaceThis, WithThis) =&gt; {
    if (!Array.isArray(arr)) throw new RangeError("Error");
    var itemSpots = [];
    for (var i = 0; i &lt; arr.length; i++) {
        if (arr[i] == replaceThis) itemSpots.push(i);
    }

    for (var i = 0; i &lt; itemSpots.length; i++) {
        arr[itemSpots[i]] = WithThis;
    }

    return arr;
};
</code></pre>


blocks|key|691327|text|presentPrompt(id,productqty)+{
++++let+alert+=+this.forgotCtrl.create({
++++++title:+'Test',
++++++inputs:+[
++++++++{
++++++++++name:+'pickqty',
++++++++++placeholder:+'pick+quantity'
++++++++},
++++++++{
++++++++++name:+'state',
++++++++++value:+'verified',
++++++++++disabled:true,
++++++++++placeholder:+'state',

++++++++}
++++++],
++++++buttons:+[
++++++++{
++++++++++text:+'Ok',
++++++++++role:+'cancel',
++++++++++handler:+data+=>+{

++++++++++++console.log('dataaaaname',data.pickqty);
++++++++++++console.log('dataaaapwd',data.state);


++++++++++for+(var+i+=+0;+i+<+this.cottonLists.length;+i%2B%2B){

++++++++++++if+(this.cottonLists[i].id+==+id){
++++++++++++++++this.cottonLists[i].real_stock+=+data.pickqty;

++++++++++++}
++++++++++}

++++++++++for+(var+i+=+0;+i+<+this.cottonLists.length;+i%2B%2B){

++++++++++++if+(this.cottonLists[i].id+==+id){
++++++++++++++this.cottonLists[i].state+=+'verified';+++

++++++++++}
++++++++}
++++++++++++//Log+object+to+console+again.
++++++++++++console.log("After+update:+",+this.cottonLists)
++++++++++++console.log('Ok+clicked');
++++++++++}
++++++++},

++++++]
++++});
++++alert.present();
++}

As+per+your+requirement+you+can+change+fields+and+array+names.
thats+all.+Enjoy+your+coding.|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|691328|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>presentPrompt(id,productqty) {
    let alert = this.forgotCtrl.create({
      title: 'Test',
      inputs: [
        {
          name: 'pickqty',
          placeholder: 'pick quantity'
        },
        {
          name: 'state',
          value: 'verified',
          disabled:true,
          placeholder: 'state',

        }
      ],
      buttons: [
        {
          text: 'Ok',
          role: 'cancel',
          handler: data =&gt; {

            console.log('dataaaaname',data.pickqty);
            console.log('dataaaapwd',data.state);


          for (var i = 0; i &lt; this.cottonLists.length; i++){

            if (this.cottonLists[i].id == id){
                this.cottonLists[i].real_stock = data.pickqty;

            }
          }

          for (var i = 0; i &lt; this.cottonLists.length; i++){

            if (this.cottonLists[i].id == id){
              this.cottonLists[i].state = 'verified';   

          }
        }
            //Log object to console again.
            console.log("After update: ", this.cottonLists)
            console.log('Ok clicked');
          }
        },

      ]
    });
    alert.present();
  }

As per your requirement you can change fields and array names.
thats all. Enjoy your coding.
</code></pre>


blocks|key|907486|text|最简单的方法是这样。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|907487|var+items+=+Array(523,3452,334,31,+5346);
var+replaceWhat+=+3452,+replaceWith+=+1010;
if+(+(+i+=+items.indexOf(replaceWhat)+)+>=0+)+items.splice(i,+1,+replaceWith);

console.log(items);
>>>+(5) [523,+1010,+334,+31,+5346]|code-block|syntax|javascript|907488|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|$]]

<p>The easiest way is this.</p>

<pre><code>var items = Array(523,3452,334,31, 5346);
var replaceWhat = 3452, replaceWith = 1010;
if ( ( i = items.indexOf(replaceWhat) ) &gt;=0 ) items.splice(i, 1, replaceWith);

console.log(items);
&gt;&gt;&gt; (5) [523, 1010, 334, 31, 5346]
</code></pre>


<p>Each item of this array is some number:</p>
<pre><code>var items = Array(523,3452,334,31, ...5346);
</code></pre>
<p>How to replace some item with a new one?</p>
<p>For example, we want to replace <code>3452</code> with <code>1010</code>, how would we do this?</p>


How to replace item in array?

JSON

该数组中的每一项都是某个数字：var items = Array(523,3452,334,31, ...5346);如何用一个新的项目替换一些项目？例如，我们想用1010替换3452，我们该怎么做呢？

问如何替换数组中的项？
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回答 23

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问如何替换数组中的项？EN

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问如何替换数组中的项？
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