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Hashtable.CopyTo(Array, Int32) Metoda

Definice

Zkopíruje elementy Hashtable do jednorozměrné Array instance v zadaném indexu.

public:
 virtual void CopyTo(Array ^ array, int arrayIndex);
public virtual void CopyTo (Array array, int arrayIndex);
abstract member CopyTo : Array * int -> unit
override this.CopyTo : Array * int -> unit
Public Overridable Sub CopyTo (array As Array, arrayIndex As Integer)

Parametry

array
Array

Jednorozměrný Array objekt, který je cílem DictionaryEntry objektů zkopírovaných z Hashtable. Musí Array mít indexování založené na nule.

arrayIndex
Int32

Index založený na nule v poli array, ve kterém kopírování začíná.

Implementuje

Výjimky

array je null.

Hodnota arrayIndex je menší než nula.

Pole array je multidimenzionální.

-nebo-

Počet prvků ve zdroji Hashtable je větší než dostupné místo od arrayIndex konce cíle array.

Typ zdroje Hashtable nelze automaticky přetypovat na typ cílového array.

Příklady

Následující příklad ukazuje, jak zkopírovat seznam klíčů nebo seznam hodnot v objektu Hashtable do jednorozměrného Arrayobjektu .

using namespace System;
using namespace System::Collections;
void PrintValues( array<String^>^myArr, char mySeparator );
int main()
{
   
   // Creates and initializes the source Hashtable.
   Hashtable^ mySourceHT = gcnew Hashtable;
   mySourceHT->Add( "A", "valueA" );
   mySourceHT->Add( "B", "valueB" );
   
   // Creates and initializes the one-dimensional target Array.
   array<String^>^myTargetArray = gcnew array<String^>(15);
   myTargetArray[ 0 ] = "The";
   myTargetArray[ 1 ] = "quick";
   myTargetArray[ 2 ] = "brown";
   myTargetArray[ 3 ] = "fox";
   myTargetArray[ 4 ] = "jumps";
   myTargetArray[ 5 ] = "over";
   myTargetArray[ 6 ] = "the";
   myTargetArray[ 7 ] = "lazy";
   myTargetArray[ 8 ] = "dog";
   
   // Displays the values of the target Array.
   Console::WriteLine( "The target Array contains the following before:" );
   PrintValues( myTargetArray, ' ' );
   
   // Copies the keys in the source Hashtable to the target Hashtable, starting at index 6.
   Console::WriteLine( "After copying the keys, starting at index 6:" );
   mySourceHT->Keys->CopyTo( myTargetArray, 6 );
   
   // Displays the values of the target Array.
   PrintValues( myTargetArray, ' ' );
   
   // Copies the values in the source Hashtable to the target Hashtable, starting at index 6.
   Console::WriteLine( "After copying the values, starting at index 6:" );
   mySourceHT->Values->CopyTo( myTargetArray, 6 );
   
   // Displays the values of the target Array.
   PrintValues( myTargetArray, ' ' );
}

void PrintValues( array<String^>^myArr, char mySeparator )
{
   for ( int i = 0; i < myArr->Length; i++ )
      Console::Write( "{0}{1}", mySeparator, myArr[ i ] );
   Console::WriteLine();
}

/* 
 This code produces the following output.
 
 The target Array contains the following before:
  The quick brown fox jumps over the lazy dog
 After copying the keys, starting at index 6:
  The quick brown fox jumps over B A dog
 After copying the values, starting at index 6:
  The quick brown fox jumps over valueB valueA dog

 */
using System;
using System.Collections;
public class SamplesHashtable
{

   public static void Main()
   {
      // Creates and initializes the source Hashtable.
      var mySourceHT = new Hashtable();
      mySourceHT.Add("A", "valueA");
      mySourceHT.Add("B", "valueB");

      // Creates and initializes the one-dimensional target Array.
      var myTargetArray = new String[15];
      myTargetArray[0] = "The";
      myTargetArray[1] = "quick";
      myTargetArray[2] = "brown";
      myTargetArray[3] = "fox";
      myTargetArray[4] = "jumps";
      myTargetArray[5] = "over";
      myTargetArray[6] = "the";
      myTargetArray[7] = "lazy";
      myTargetArray[8] = "dog";

      // Displays the values of the target Array.
      Console.WriteLine("The target Array contains the following before:");
      PrintValues(myTargetArray, ' ');

      // Copies the keys in the source Hashtable to the target Hashtable, starting at index 6.
      Console.WriteLine("After copying the keys, starting at index 6:");
      mySourceHT.Keys.CopyTo(myTargetArray, 6);

      // Displays the values of the target Array.
      PrintValues(myTargetArray, ' ');

      // Copies the values in the source Hashtable to the target Hashtable, starting at index 6.
      Console.WriteLine("After copying the values, starting at index 6:");
      mySourceHT.Values.CopyTo(myTargetArray, 6);

      // Displays the values of the target Array.
      PrintValues(myTargetArray, ' ');
   }

   public static void PrintValues(String[] myArr, char mySeparator)
   {
      for (int i = 0; i < myArr.Length; i++)
         Console.Write($"{mySeparator}{myArr[i]}");
      Console.WriteLine();
   }
}
/*
This code produces the following output.

The target Array contains the following before:
 The quick brown fox jumps over the lazy dog
After copying the keys, starting at index 6:
 The quick brown fox jumps over B A dog
After copying the values, starting at index 6:
 The quick brown fox jumps over valueB valueA dog

*/
Imports System.Collections

Public Class SamplesHashtable

    Public Shared Sub Main()

        ' Creates and initializes the source Hashtable.
        Dim mySourceHT As New Hashtable()
        mySourceHT.Add("A", "valueA")
        mySourceHT.Add("B", "valueB")

        ' Creates and initializes the one-dimensional target Array.
        Dim myTargetArray(14) As String
        myTargetArray(0) = "The"
        myTargetArray(1) = "quick"
        myTargetArray(2) = "brown"
        myTargetArray(3) = "fox"
        myTargetArray(4) = "jumps"
        myTargetArray(5) = "over"
        myTargetArray(6) = "the"
        myTargetArray(7) = "lazy"
        myTargetArray(8) = "dog"

        ' Displays the values of the target Array.
        Console.WriteLine("The target Array contains the following before:")
        PrintValues(myTargetArray, " "c)

        ' Copies the keys in the source Hashtable to the target Hashtable, starting at index 6.
        Console.WriteLine("After copying the keys, starting at index 6:")
        mySourceHT.Keys.CopyTo(myTargetArray, 6)

        ' Displays the values of the target Array.
        PrintValues(myTargetArray, " "c)

        ' Copies the values in the source Hashtable to the target Hashtable, starting at index 6.
        Console.WriteLine("After copying the values, starting at index 6:")
        mySourceHT.Values.CopyTo(myTargetArray, 6)

        ' Displays the values of the target Array.
        PrintValues(myTargetArray, " "c)

    End Sub

    Public Shared Sub PrintValues(myArr As String(), mySeparator As Char)
        For i As Integer = 0 To myArr.Length - 1
            Console.Write($"{mySeparator}{myArr(i)}")
        Next i
        Console.WriteLine()
    End Sub

End Class


' This code produces the following output.
' 
' The target Array contains the following before:
'  The quick brown fox jumps over the lazy dog
' After copying the keys, starting at index 6:
'  The quick brown fox jumps over A B dog
' After copying the values, starting at index 6:
'  The quick brown fox jumps over valueA valueB dog

Poznámky

Prvky se zkopírují do objektu Array ve stejném pořadí, ve kterém iterátor výčtu prochází .Hashtable

Pokud chcete zkopírovat pouze klíče v nástroji Hashtable, použijte Hashtable.Keys.CopyTo.

Chcete-li zkopírovat pouze hodnoty v Hashtable, použijte Hashtable.Values.CopyTo.

Tato metoda je O(n) operace, kde n je Count.

Platí pro

Viz také