StringCollection.Insert(Int32, String) Méthode
Définition
Important
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Insère une chaîne dans StringCollection à l'index spécifié.
public:
void Insert(int index, System::String ^ value);
public void Insert (int index, string value);
public void Insert (int index, string? value);
member this.Insert : int * string -> unit
Public Sub Insert (index As Integer, value As String)
Paramètres
- index
- Int32
Index de base zéro au niveau duquel value
est inséré.
- value
- String
Chaîne à insérer. La valeur peut être null
.
Exceptions
Exemples
L’exemple de code suivant ajoute de nouveaux éléments à .StringCollection
#using <System.dll>
using namespace System;
using namespace System::Collections;
using namespace System::Collections::Specialized;
void PrintValues( IEnumerable^ myCol );
int main()
{
// Creates and initializes a new StringCollection.
StringCollection^ myCol = gcnew StringCollection;
Console::WriteLine( "Initial contents of the StringCollection:" );
PrintValues( myCol );
// Adds a range of elements from an array to the end of the StringCollection.
array<String^>^myArr = {"RED","orange","yellow","RED","green","blue","RED","indigo","violet","RED"};
myCol->AddRange( myArr );
Console::WriteLine( "After adding a range of elements:" );
PrintValues( myCol );
// Adds one element to the end of the StringCollection and inserts another at index 3.
myCol->Add( "* white" );
myCol->Insert( 3, "* gray" );
Console::WriteLine( "After adding \"* white\" to the end and inserting \"* gray\" at index 3:" );
PrintValues( myCol );
}
void PrintValues( IEnumerable^ myCol )
{
IEnumerator^ myEnum = myCol->GetEnumerator();
while ( myEnum->MoveNext() )
{
Object^ obj = safe_cast<Object^>(myEnum->Current);
Console::WriteLine( " {0}", obj );
}
Console::WriteLine();
}
/*
This code produces the following output.
Initial contents of the StringCollection:
After adding a range of elements:
RED
orange
yellow
RED
green
blue
RED
indigo
violet
RED
After adding "* white" to the end and inserting "* gray" at index 3:
RED
orange
yellow
* gray
RED
green
blue
RED
indigo
violet
RED
* white
*/
using System;
using System.Collections;
using System.Collections.Specialized;
public class SamplesStringCollection {
public static void Main() {
// Creates and initializes a new StringCollection.
StringCollection myCol = new StringCollection();
Console.WriteLine( "Initial contents of the StringCollection:" );
PrintValues( myCol );
// Adds a range of elements from an array to the end of the StringCollection.
String[] myArr = new String[] { "RED", "orange", "yellow", "RED", "green", "blue", "RED", "indigo", "violet", "RED" };
myCol.AddRange( myArr );
Console.WriteLine( "After adding a range of elements:" );
PrintValues( myCol );
// Adds one element to the end of the StringCollection and inserts another at index 3.
myCol.Add( "* white" );
myCol.Insert( 3, "* gray" );
Console.WriteLine( "After adding \"* white\" to the end and inserting \"* gray\" at index 3:" );
PrintValues( myCol );
}
public static void PrintValues( IEnumerable myCol ) {
foreach ( Object obj in myCol )
Console.WriteLine( " {0}", obj );
Console.WriteLine();
}
}
/*
This code produces the following output.
Initial contents of the StringCollection:
After adding a range of elements:
RED
orange
yellow
RED
green
blue
RED
indigo
violet
RED
After adding "* white" to the end and inserting "* gray" at index 3:
RED
orange
yellow
* gray
RED
green
blue
RED
indigo
violet
RED
* white
*/
Imports System.Collections
Imports System.Collections.Specialized
Public Class SamplesStringCollection
Public Shared Sub Main()
' Creates and initializes a new StringCollection.
Dim myCol As New StringCollection()
Console.WriteLine("Initial contents of the StringCollection:")
PrintValues(myCol)
' Adds a range of elements from an array to the end of the StringCollection.
Dim myArr() As [String] = {"RED", "orange", "yellow", "RED", "green", "blue", "RED", "indigo", "violet", "RED"}
myCol.AddRange(myArr)
Console.WriteLine("After adding a range of elements:")
PrintValues(myCol)
' Adds one element to the end of the StringCollection and inserts another at index 3.
myCol.Add("* white")
myCol.Insert(3, "* gray")
Console.WriteLine("After adding ""* white"" to the end and inserting ""* gray"" at index 3:")
PrintValues(myCol)
End Sub
Public Shared Sub PrintValues(myCol As IEnumerable)
Dim obj As [Object]
For Each obj In myCol
Console.WriteLine(" {0}", obj)
Next obj
Console.WriteLine()
End Sub
End Class
'This code produces the following output.
'
'Initial contents of the StringCollection:
'
'After adding a range of elements:
' RED
' orange
' yellow
' RED
' green
' blue
' RED
' indigo
' violet
' RED
'
'After adding "* white" to the end and inserting "* gray" at index 3:
' RED
' orange
' yellow
' * gray
' RED
' green
' blue
' RED
' indigo
' violet
' RED
' * white
'
Remarques
Les chaînes en double sont autorisées dans StringCollection.
Si index
est égal à Count, value
est ajouté à la fin de StringCollection.
Dans des collections d’éléments contigus, telles que les listes, les éléments situés après le point d’insertion descendent afin de prendre en compte le nouvel élément. Si la collection est indexée, les index des éléments déplacés sont également mis à jour. Ce comportement ne s'applique pas aux collections dont les éléments sont regroupés de manière conceptuelle en compartiments, comme par exemple les tables de hachage.
Cette méthode est une opération O(n
), où n
est Count.