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String.GetEnumerator Method

Definition

Retrieves an object that can iterate through the individual characters in this string.

C#
public CharEnumerator GetEnumerator();

Returns

An enumerator object.

Examples

The following example iterates the characters in several strings and displays information about their individual characters. It uses the language iteration construct rather than a call to the GetEnumerator method.

C#
using System;

class Example
{
   public static void Main() 
   {
      EnumerateAndDisplay("Test Case");
      EnumerateAndDisplay("This is a sentence.");
      EnumerateAndDisplay("Has\ttwo\ttabs" );
      EnumerateAndDisplay("Two\nnew\nlines");
   }

   static void EnumerateAndDisplay(String phrase)
   {
      Console.WriteLine("The characters in the string \"{0}\" are:",
                        phrase);

      int CharCount = 0;
      int controlChars = 0;
      int alphanumeric = 0;
      int punctuation = 0;

      foreach (var ch in phrase) {
         Console.Write(Char.IsControl(ch) ? $"{ch}" : $"0x{(ushort)ch:X4}");

         if (Char.IsLetterOrDigit(ch)) 
            alphanumeric++;
         else if (Char.IsControl(ch)) 
            controlChars++;
         else if (Char.IsPunctuation(ch)) 
            punctuation++;             
         CharCount++;
      }

      Console.WriteLine("\n   Total characters:        {0,3}", CharCount);
      Console.WriteLine("   Alphanumeric characters: {0,3}", alphanumeric);
      Console.WriteLine("   Punctuation characters:  {0,3}", punctuation);
      Console.WriteLine("   Control Characters:      {0,3}\n", controlChars);
   }
}
// The example displays the following output:
//    The characters in the string "Test Case" are:
//    'T' 'e' 's' 't' ' ' 'C' 'a' 's' 'e'
//       Total characters:          9
//       Alphanumeric characters:   8
//       Punctuation characters:    0
//       Control Characters:        0
//    
//    The characters in the string "This is a sentence." are:
//    'T' 'h' 'i' 's' ' ' 'i' 's' ' ' 'a' ' ' 's' 'e' 'n' 't' 'e' 'n' 'c' 'e' '.'
//       Total characters:         19
//       Alphanumeric characters:  15
//       Punctuation characters:    1
//       Control Characters:        0
//    
//    The characters in the string "Has       two     tabs" are:
//    'H' 'a' 's' '0x0009' 't' 'w' 'o' '0x0009' 't' 'a' 'b' 's'
//       Total characters:         12
//       Alphanumeric characters:  10
//       Punctuation characters:    0
//       Control Characters:        2
//    
//    The characters in the string "Two
//    new
//    lines" are:
//    'T' 'w' 'o' '0x000A' 'n' 'e' 'w' '0x000A' 'l' 'i' 'n' 'e' 's'
//       Total characters:         13
//       Alphanumeric characters:  11
//       Punctuation characters:    0
//       Control Characters:        2

Remarks

Prepitné

Rather than calling the GetEnumerator method to retrieve a CharEnumerator object that you then use to enumerate a string, you should instead use your language's iteration construct (in C#, in F#, in C++/CLR, and in Visual Basic). foreach in C#, for..in in F#, for each in C++/CLR, and For Each in Visual Basic).

This method enables you to iterate the individual characters in a string. For example, the Visual Basic For Each, the F# for..in expression, and C# foreach statements invoke this method to return a CharEnumerator object that can provide read-only access to the characters in this string instance.

Applies to

Produkt Verzie
.NET Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework 1.1, 2.0, 3.0, 3.5, 4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard 2.0, 2.1

See also