Csharp/CSharp Tutorial/Data Structure/Array Search

Use the BinarySearch() method to search charArray for "o"

<source lang="csharp">using System; class MainClass {

 public static void Main()
 {
   char[] charArray = {"w", "e", "l", "c", "o", "m", "e"};
   Array.Sort(charArray);  // sort the elements        
   int index = Array.BinarySearch(charArray, "o");
   Console.WriteLine("Array.BinarySearch(charArray, "o") = " + index);
 }

}</source>

Array.BinarySearch(charArray, "o") = 5

Use the BinarySearch() method to search intArray for the number 4: BinarySearch() returns a negative value

<source lang="csharp">using System; class MainClass {

 public static void Main()
 {
   int[] intArray = {5, 2, 3, 1, 6, 9, 7, 14, 25};
   Array.Sort(intArray);
   
   int index = Array.BinarySearch(intArray, 4);
   Console.WriteLine("Array.BinarySearch(intArray, 4) = " + index);
 }

}</source>

Array.BinarySearch(intArray, 4) = -4

Use the BinarySearch() method to search intArray for the number 5

<source lang="csharp">using System; class MainClass {

 public static void Main()
 {
   int[] intArray = {5, 2, 3, 1, 6, 9, 7, 14, 25};
   Array.Sort(intArray);
   
   int index = Array.BinarySearch(intArray, 5);
   Console.WriteLine("Array.BinarySearch(intArray, 5) = " + index);
 }

}</source>

Array.BinarySearch(intArray, 5) = 3

Use the BinarySearch() method to search stringArray for "abc345"

<source lang="csharp">using System; class MainClass {

 public static void Main()
 {
   string[] stringArray = {"t", "i", "a", "test", "abc123", "abc345"};
   Array.Sort(stringArray);
       
   int index = Array.BinarySearch(stringArray, "abc345");
   Console.WriteLine("Array.BinarySearch(stringArray, \"abc345\") = " + index);
 }

}</source>

Array.BinarySearch(stringArray, "abc345") = 2