CharEnumerator.MoveNext Méthode

Définition

Incrémente l'index interne de l'objet CharEnumerator actuel jusqu'au caractère suivant de la chaîne énumérée.Increments the internal index of the current CharEnumerator object to the next character of the enumerated string.

public:
 virtual bool MoveNext();
public bool MoveNext ();
abstract member MoveNext : unit -> bool
override this.MoveNext : unit -> bool
Public Function MoveNext () As Boolean

Retours

true si l'index est incrémenté avec succès dans la chaîne énumérée ; sinon, false.true if the index is successfully incremented and within the enumerated string; otherwise, false.

Implémente

Exemples

L’exemple suivant utilise la classe CharEnumerator pour énumérer les caractères individuels d’une chaîne.The following example uses the CharEnumerator class to enumerate the individual characters in a string. Il instancie un objet CharEnumerator en appelant la méthode String.GetEnumerator, passe d’un caractère à l’autre en appelant la méthode MoveNext et affiche le caractère actuel en extrayant la valeur de la propriété Current.It instantiates a CharEnumerator object by calling the String.GetEnumerator method, moves from one character to the next by calling the MoveNext method, and displays the current character by retrieving the value of the Current property.

String ^ title = "A Tale of Two Cities";
CharEnumerator ^ chEnum = title->GetEnumerator();
int ctr = 1;
String ^ outputLine1 = nullptr;
String ^ outputLine2 = nullptr;
String ^ outputLine3 = nullptr; 

while (chEnum->MoveNext())
{
   outputLine1 += ctr < 10 || ctr % 10 != 0 ? "  " : (ctr / 10) + " ";
   outputLine2 += (ctr % 10) + " ";
   outputLine3 += chEnum->Current + " ";
   ctr++;
}

Console::WriteLine("The length of the string is {0} characters:", 
                  title->Length);
Console::WriteLine(outputLine1);
Console::WriteLine(outputLine2);    
Console::WriteLine(outputLine3);
// The example displays the following output to the console:      
//       The length of the string is 20 characters:
//                         1                   2
//       1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
//       A   T a l e   o f   T w o   C i t i e s
string title = "A Tale of Two Cities";
CharEnumerator chEnum = title.GetEnumerator();
int ctr = 1;
string outputLine1 = null;
string outputLine2 = null;
string outputLine3 = null; 

while (chEnum.MoveNext())
{
   outputLine1 += ctr < 10 || ctr % 10 != 0 ? "  " : (ctr / 10) + " ";
   outputLine2 += (ctr % 10) + " ";
   outputLine3 += chEnum.Current + " ";
   ctr++;
}

Console.WriteLine("The length of the string is {0} characters:", 
                  title.Length);
Console.WriteLine(outputLine1);
Console.WriteLine(outputLine2);    
Console.WriteLine(outputLine3);
// The example displays the following output to the console:      
//       The length of the string is 20 characters:
//                         1                   2
//       1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
//       A   T a l e   o f   T w o   C i t i e s
Dim title As String = "A Tale of Two Cities"
Dim chEnum As CharEnumerator = title.GetEnumerator()
Dim ctr As Integer = 1
Dim outputLine1, outputLine2, outputLine3 As String 

Do While chEnum.MoveNext()
   outputLine1 += CStr(iif(ctr < 10 Or ctr Mod 10 <> 0, "  ", CStr(ctr \ 10) + " ")) 
   outputLine2 += (ctr Mod 10)& " "
   outputLine3 += chEnum.Current & " "
   ctr += 1
Loop

Console.WriteLine("The length of the string is {0} characters:", _
                  title.Length)
Console.WriteLine(outputLine1)
Console.WriteLine(outputLine2)    
Console.WriteLine(outputLine3)
' The example displays the following output to the console:      
'       The length of the string is 20 characters:
'                         1                   2
'       1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
'       A   T a l e   o f   T w o   C i t i e s

Notez, toutefois, que la même opération peut être effectuée un peu plus intuitivement en utilisant foreach ( C#dans) ou For Each (dans Visual Basic), comme le montre l’exemple suivant.Note, however, that the same operation can be performed somewhat more intuitively by using foreach (in C#) or For Each (in Visual Basic), as the following example shows.

String ^ title = "A Tale of Two Cities";
int ctr = 1;
String ^ outputLine1 = nullptr;
String ^ outputLine2 = nullptr;
String ^ outputLine3 = nullptr; 

for each (wchar_t ch in title)
{
   outputLine1 += ctr < 10 || ctr % 10 != 0 ? "  " : (ctr / 10) + " ";
   outputLine2 += (ctr % 10) + " ";
   outputLine3 += ch + " ";
   ctr++;
}

Console::WriteLine("The length of the string is {0} characters:", 
                  title->Length);
Console::WriteLine(outputLine1);
Console::WriteLine(outputLine2);    
Console::WriteLine(outputLine3);
// The example displays the following output to the console:      
//       The length of the string is 20 characters:
//                         1                   2
//       1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
//       A   T a l e   o f   T w o   C i t i e s
string title = "A Tale of Two Cities";
int ctr = 1;
string outputLine1 = null;
string outputLine2 = null;
string outputLine3 = null; 

foreach (char ch in title)
{
   outputLine1 += ctr < 10 || ctr % 10 != 0 ? "  " : (ctr / 10) + " ";
   outputLine2 += (ctr % 10) + " ";
   outputLine3 += ch + " ";
   ctr++;
}

Console.WriteLine("The length of the string is {0} characters:", 
                  title.Length);
Console.WriteLine(outputLine1);
Console.WriteLine(outputLine2);    
Console.WriteLine(outputLine3);
// The example displays the following output to the console:      
//       The length of the string is 20 characters:
//                         1                   2
//       1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
//       A   T a l e   o f   T w o   C i t i e s
Dim title As String = "A Tale of Two Cities"
Dim ctr As Integer = 1
Dim outputLine1, outputLine2, outputLine3 As String 

For Each ch As Char In title
   outputLine1 += CStr(iif(ctr < 10 Or ctr Mod 10 <> 0, "  ", CStr(ctr \ 10) + " ")) 
   outputLine2 += (ctr Mod 10)& " "
   outputLine3 += ch & " "
   ctr += 1
Next

Console.WriteLine("The length of the string is {0} characters:", _
                  title.Length)
Console.WriteLine(outputLine1)
Console.WriteLine(outputLine2)    
Console.WriteLine(outputLine3)
' The example displays the following output to the console:      
'       The length of the string is 20 characters:
'                         1                   2
'       1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0
'       A   T a l e   o f   T w o   C i t i e s

Remarques

La classe CharEnumerator conserve un index interne à la chaîne énumérée, et la méthode MoveNext incrémente l’index d’une unité.The CharEnumerator class maintains an internal index to the enumerated string, and the MoveNext method increments the index by one. Appelez MoveNext après avoir appelé GetEnumerator ou Reset pour incrémenter la position actuelle du caractère dans le premier caractère de la chaîne énumérée.Call MoveNext after calling GetEnumerator or Reset to increment the current character position to the first character in the enumerated string. Vérifiez que la valeur de retour est true pour déterminer que la position actuelle du caractère est valide.Check that the return value is true to determine that the current character position is valid.

Si l’index est déjà au-delà du dernier caractère de la chaîne énumérée, l’index n’est pas modifié et false est retourné.If the index is already beyond the last character of the enumerated string, the index is not changed and false is returned.

Notez que si la chaîne énumérée est vide (""), l’état de la CharEnumerator est toujours non valide.Notice that if the enumerated string is empty (""), the state of the CharEnumerator is always invalid. Cela est dû au fait que l’index interne pour le CharEnumerator est initialement avant le premier caractère de la chaîne énumérée et n’est donc pas valide.This is because the internal index for the CharEnumerator is initially before the first character of the enumerated string and is therefore invalid. MoveNext définit logiquement l’index après le dernier caractère (inexistant) de la chaîne énumérée qui n’est pas non plus valide.MoveNext logically sets the index after the last (nonexistent) character of the enumerated string which is also invalid.

S’applique à