blocks|key|579813|text|string[]+myarr+=+new+string[]+{"s",+"f",+"s"};

int[]+v+=+myarr.Select((b,i)+=>+b+==+"s"+?+i+:+-1).Where(i+=>+i+!=+-1).ToArray();|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|579814|这将返回0，2|unstyled|579815|如果数组中不存在该值，则它将返回一个int。|579816|创建它的扩展方法|579817|public+static+class+EM
{
++++public+static+int[]+FindAllIndexof<T>(this+IEnumerable<T>+values,+T+val)
++++{
++++++++return+values.Select((b,i)+=>+object.Equals(b,+val)+?+i+:+-1).Where(i+=>+i+!=+-1).ToArray();
++++}
}|579818|并将其命名为|579819|string[]+myarr+=+new+string[]+{"s",+"f",+"s"};

int[]+v+=+myarr.FindAllIndexof("s");|579820|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|T|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|U|8|@]|9|@]|A|$]]|$1|I|3|J|5|F|7|V|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|W|8|@]|9|@]|A|$B|C]]|$1|M|3|N|5|F|7|X|8|@]|9|@]|A|$]]|$1|O|3|P|5|6|7|Y|8|@]|9|@]|A|$B|C]]|$1|Q|3|-4|5|F|7|Z|8|@]|9|@]|A|$]]]|R|$]]

<pre><code>string[] myarr = new string[] {"s", "f", "s"};

int[] v = myarr.Select((b,i) =&gt; b == "s" ? i : -1).Where(i =&gt; i != -1).ToArray();
</code></pre>

This will return 0, 2

If the value does not exist in the array then it will return a int[0].

make an extension method of it

<pre><code>public static class EM
{
 public static int[] FindAllIndexof&lt;T&gt;(this IEnumerable&lt;T&gt; values, T val)
 {
 return values.Select((b,i) =&gt; object.Equals(b, val) ? i : -1).Where(i =&gt; i != -1).ToArray();
 }
}
</code></pre>

and call it like

<pre><code>string[] myarr = new string[] {"s", "f", "s"};

int[] v = myarr.FindAllIndexof("s");
</code></pre>

blocks|key|579919|text|搜索与指定谓词定义的条件匹配的元素，并返回整个System.Array内该匹配项的所有从零开始的索引。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|579920|public+static+int[]+FindAllIndex<T>(this+T[]+array,+Predicate<T>+match)
{
++++return+array.Select((value,+index)+=>+match(value)+?+index+:+-1)
++++++++++++.Where(index+=>+index+!=+-1).ToArray();
}|code-block|syntax|javascript|579921|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|$]]

Searches for an element that matches the conditions defined by the specified predicate, and returns all the zero-based index of the occurrence within the entire System.Array.

<pre><code>public static int[] FindAllIndex&lt;T&gt;(this T[] array, Predicate&lt;T&gt; match)
{
 return array.Select((value, index) =&gt; match(value) ? index : -1)
 .Where(index =&gt; index != -1).ToArray();
}
</code></pre>

blocks|key|579874|text|不，没有。但您可以编写自己的extension+method。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|579875|public+static+int[]+FindAllIndexOf<T>(this+T[]+a,+Predicate<T>+match)
{
+++T[]+subArray+=+Array.FindAll<T>(a,+match);
+++return+(from+T+item+in+subArray+select+Array.IndexOf(a,+item)).ToArray();
}|code-block|syntax|javascript|579876|然后，对于您的数组，调用它。|579877|entityMap|0|LINK|mutability|MUTABLE|url|http://msdn.microsoft.com/en-us/library/bb383977.aspx^0|E|G|0|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@]|9|@$A|T|B|U|1|V]]|C|$]]|$1|D|3|E|5|F|7|W|8|@]|9|@]|C|$G|H]]|$1|I|3|J|5|6|7|X|8|@]|9|@]|C|$]]|$1|K|3|-4|5|6|7|Y|8|@]|9|@]|C|$]]]|L|$M|$5|N|O|P|C|$Q|R]]]]

No, there is not. But you can write your own <a href="http://msdn.microsoft.com/en-us/library/bb383977.aspx" rel="nofollow">extension method</a>.

<pre><code>public static int[] FindAllIndexOf&lt;T&gt;(this T[] a, Predicate&lt;T&gt; match)
{
 T[] subArray = Array.FindAll&lt;T&gt;(a, match);
 return (from T item in subArray select Array.IndexOf(a, item)).ToArray();
}
</code></pre>

and then, for your array, call it.

blocks|key|579845|text|您可以使用findIndex给出一个索引进行循环|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|579846|string[]+arr+=+{+"abc",+"asd",+"def",+"abc",+"lmn",+"wer"+};
int+index+=+-1;
do
{
++++index+=+Array.IndexOf(arr,+"abc",+index+%2B+1);
++++System.Console.WriteLine(index);
}+while+(-1+!=+index);|code-block|syntax|javascript|579847|entityMap|0|LINK|mutability|MUTABLE|url|http://msdn.microsoft.com/en-us/library/xhdxx3we.aspx^0|5|9|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]]]]

You can loop with <a href="http://msdn.microsoft.com/en-us/library/xhdxx3we.aspx" rel="nofollow">findIndex</a> giving an index

<pre><code>string[] arr = { "abc", "asd", "def", "abc", "lmn", "wer" };
int index = -1;
do
{
 index = Array.IndexOf(arr, "abc", index + 1);
 System.Console.WriteLine(index);
} while (-1 != index);
</code></pre>

blocks|key|580049|text|我已经使用Nikhil+Agrawal的答案创建了下面的相关方法，这可能是有用的。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|580050|public+static+List<int>+FindAllIndexOf<T>(List<T>+values,+List<T>+matches)
++++{
++++++++//+Initialize+list
++++++++List<int>+index+=+new+List<int>();

++++++++//+For+each+value+in+matches+get+the+index+and+add+to+the+list+with+indexes
++++++++foreach+(var+match+in+matches)
++++++++{
++++++++++++//+Find+matches+
++++++++++++index.AddRange(values.Select((b,+i)+=>+Equals(b,+match)+?+i+:+-1).Where(i+=>+i+!=+-1).ToList());

++++++++}

++++++++return+index;
++++}|code-block|syntax|javascript|580051|它包含一个包含值的列表和一个包含要匹配的值的列表。它返回一个带有匹配索引的整数列表。|580052|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

I've used Nikhil Agrawal's answer to create the following related method, which may be useful.

<pre><code>public static List&lt;int&gt; FindAllIndexOf&lt;T&gt;(List&lt;T&gt; values, List&lt;T&gt; matches)
 {
 // Initialize list
 List&lt;int&gt; index = new List&lt;int&gt;();

 // For each value in matches get the index and add to the list with indexes
 foreach (var match in matches)
 {
 // Find matches 
 index.AddRange(values.Select((b, i) =&gt; Equals(b, match) ? i : -1).Where(i =&gt; i != -1).ToList());

 }

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

Which takes a list with values and a list with values that are to be matched. It returns a list of integers with the index of the matches.

blocks|key|364226|text|你可以通过只创建2个整数变量来解决这个问题。给你更多的力量！|type|unstyled|depth|inlineStyleRanges|entityRanges|data|364227|string[]+seasons=+{+"Fall","Spring",+"Summer",+"Fall",+"Fall",+"Winter"};

int+i+=+0;

int+IndexOfFallInArray+=+0;

int[]+IndexesOfFall=+new+int[seasons.Length];

foreach+(var+item+in+seasons)
{
++++if+(item+==+"Fall")
++++++++{
++++++++++++IndexesOfFall[i]+=+IndexOfFallInArray;
++++++++++++i%2B%2B;
++++++++}
++++++++IndexOfFallInArray%2B%2B;
}|code-block|syntax|javascript|364228|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|$]]

You can solve this problem by creating only 2 integer variables. More power to you! 

<pre><code>string[] seasons= { "Fall","Spring", "Summer", "Fall", "Fall", "Winter"};

int i = 0;

int IndexOfFallInArray = 0;

int[] IndexesOfFall= new int[seasons.Length];

foreach (var item in seasons)
{
 if (item == "Fall")
 {
 IndexesOfFall[i] = IndexOfFallInArray;
 i++;
 }
 IndexOfFallInArray++;
}
</code></pre>

blocks|key|579983|text|我意识到这个问题已经得到了回答，这只是另一种方式。请注意，我使用的是ArrayList而不是int[]|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|579984|//+required+using+directives
using+System;
using+System.Collections;

String++++++inputString+=+"The+lazy+fox+couldn't+jump,+poor+fox!";
ArrayList+++locations+++=++new+ArrayList();++++++//+array+for+found+indexes
string[]+lineArray+=+inputString.Split('+');+++++//+inputString+to+array+of+strings+separated+by+spaces

int+tempInt+=+0;
foreach+(string+element+in+lineArray)
{
+++++if+(element+==+"fox")
+++++{
+++++++++locations.Add(tempInt);+++//+tempInt+will+be+the+index+of+current+found+index+and+added+to+Arraylist+for+further+processing+
+++++}
+tempInt%2B%2B;
}|code-block|syntax|javascript|579985|entityMap^0|Y|9|1A|5|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]|$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|L|$]]

I'm aware that the question is answered already, this is just another way of doing it. note that I used <code>ArrayList</code> instead of <code>int[]</code>

<pre><code>// required using directives
using System;
using System.Collections;

String inputString = "The lazy fox couldn't jump, poor fox!";
ArrayList locations = new ArrayList(); // array for found indexes
string[] lineArray = inputString.Split(' '); // inputString to array of strings separated by spaces

int tempInt = 0;
foreach (string element in lineArray)
{
 if (element == "fox")
 {
 locations.Add(tempInt); // tempInt will be the index of current found index and added to Arraylist for further processing 
 }
 tempInt++;
}
</code></pre>

I know c# has <a href="http://msdn.microsoft.com/en-us/library/1kkxfxdd.aspx"><code>Array.FindAll</code></a> and <a href="http://msdn.microsoft.com/en-us/library/system.array.indexof.aspx"><code>Array.IndexOf</code></a>.

Is there a <code>Array.FindAllIndexOf</code> which returns <code>int[]</code>?

c# Array.FindAllIndexOf which FindAll IndexOf

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问c# Array.FindAllIndexOf which IndexOf
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问c# Array.FindAllIndexOf which IndexOf
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