String.GetEnumerator Method ()
Retrieves an object that can iterate through the individual characters in this string.
Assembly: mscorlib (in mscorlib.dll)
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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 C++/CLR, and in Visual Basic). foreach in C#, 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 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.
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.
Module Example Sub Main() EnumerateAndDisplay("Test Case") EnumerateAndDisplay("This is a sentence.") EnumerateAndDisplay("Has" & vbTab & "two" & vbTab & "tabs") EnumerateAndDisplay("Two" & vbLf & "new" & vbLf & "lines") End Sub Sub EnumerateAndDisplay(phrase As String) Console.WriteLine("The characters in the string ""{0}"" are:", phrase) Dim charCount As Integer = 0 Dim controlChars As Integer = 0 Dim alphanumeric As Integer = 0 Dim punctuation As Integer = 0 For Each ch In phrase Console.Write("'{0}' ", If(Not Char.IsControl(ch), ch, "0x" + Convert.ToUInt16(ch).ToString("X4"))) If Char.IsLetterOrDigit(ch) Then alphanumeric += 1 Else If Char.IsControl(ch) Then controlChars += 1 Else If Char.IsPunctuation(ch) Then punctuation += 1 End If CharCount += 1 Next Console.WriteLine() Console.WriteLine(" 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}", controlChars) Console.WriteLine() End Sub End Module ' This 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
Available since 1.1
