ArrayList.IndexOf Methode
Definition
Wichtig
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Gibt den nullbasierten Index des ersten Vorkommens eines Werts in der ArrayList bzw. in einem Abschnitt davon zurück.
Überlädt
| IndexOf(Object) |
Sucht nach dem angegebenen Object und gibt den nullbasierten Index des ersten Vorkommens innerhalb der gesamten ArrayList zurück. |
| IndexOf(Object, Int32) |
Sucht nach dem angegebenen Object und gibt den nullbasierten Index des ersten Vorkommens innerhalb des Bereichs von Elementen in der ArrayList zurück, der sich vom angegebenen Index bis zum letzten Element erstreckt. |
| IndexOf(Object, Int32, Int32) |
Sucht nach dem angegebenen Object und gibt den nullbasierten Index des ersten Vorkommens innerhalb des Bereichs von Elementen in der ArrayList zurück, der am angegebenen Index beginnt und die angegebene Anzahl von Elementen enthält. |
IndexOf(Object)
- Quelle:
- ArrayList.cs
- Quelle:
- ArrayList.cs
- Quelle:
- ArrayList.cs
public:
virtual int IndexOf(System::Object ^ value);public virtual int IndexOf (object value);public virtual int IndexOf (object? value);abstract member IndexOf : obj -> int
override this.IndexOf : obj -> intPublic Overridable Function IndexOf (value As Object) As IntegerParameter
Gibt zurück
Der nullbasierte Index des ggf. ersten Vorkommens von value in der gesamten ArrayList, andernfalls -1.
Implementiert
Beispiele
Im folgenden Codebeispiel wird gezeigt, wie der Index des ersten Vorkommens eines angegebenen Elements bestimmt wird.
using namespace System;
using namespace System::Collections;
void PrintIndexAndValues( IEnumerable^ myList );
int main()
{
// Creates and initializes a new ArrayList with three elements of the same value.
ArrayList^ myAL = gcnew ArrayList;
myAL->Add( "the" );
myAL->Add( "quick" );
myAL->Add( "brown" );
myAL->Add( "fox" );
myAL->Add( "jumps" );
myAL->Add( "over" );
myAL->Add( "the" );
myAL->Add( "lazy" );
myAL->Add( "dog" );
myAL->Add( "in" );
myAL->Add( "the" );
myAL->Add( "barn" );
// Displays the values of the ArrayList.
Console::WriteLine( "The ArrayList contains the following values:" );
PrintIndexAndValues( myAL );
// Search for the first occurrence of the duplicated value.
String^ myString = "the";
int myIndex = myAL->IndexOf( myString );
Console::WriteLine( "The first occurrence of \"{0}\" is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in the last section of the ArrayList.
myIndex = myAL->IndexOf( myString, 4 );
Console::WriteLine( "The first occurrence of \"{0}\" between index 4 and the end is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in a section of the ArrayList.
myIndex = myAL->IndexOf( myString, 6, 6 );
Console::WriteLine( "The first occurrence of \"{0}\" between index 6 and index 11 is at index {1}.", myString, myIndex );
}
void PrintIndexAndValues( IEnumerable^ myList )
{
int i = 0;
IEnumerator^ myEnum = myList->GetEnumerator();
while ( myEnum->MoveNext() )
{
Object^ obj = safe_cast<Object^>(myEnum->Current);
Console::WriteLine( " [{0}]: {1}", i++, obj );
}
Console::WriteLine();
}
/*
This code produces the following output.
The ArrayList contains the following values:
[0]: the
[1]: quick
[2]: brown
[3]: fox
[4]: jumps
[5]: over
[6]: the
[7]: lazy
[8]: dog
[9]: in
[10]: the
[11]: barn
The first occurrence of "the" is at index 0.
The first occurrence of "the" between index 4 and the end is at index 6.
The first occurrence of "the" between index 6 and index 11 is at index 6.
*/
using System;
using System.Collections;
public class SamplesArrayList
{
public static void Main()
{
// Creates and initializes a new ArrayList with three elements of the same value.
ArrayList myAL = new ArrayList();
myAL.Add( "the" );
myAL.Add( "quick" );
myAL.Add( "brown" );
myAL.Add( "fox" );
myAL.Add( "jumps" );
myAL.Add( "over" );
myAL.Add( "the" );
myAL.Add( "lazy" );
myAL.Add( "dog" );
myAL.Add( "in" );
myAL.Add( "the" );
myAL.Add( "barn" );
// Displays the values of the ArrayList.
Console.WriteLine( "The ArrayList contains the following values:" );
PrintIndexAndValues( myAL );
// Search for the first occurrence of the duplicated value.
string myString = "the";
int myIndex = myAL.IndexOf( myString );
Console.WriteLine( "The first occurrence of \"{0}\" is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in the last section of the ArrayList.
myIndex = myAL.IndexOf( myString, 4 );
Console.WriteLine( "The first occurrence of \"{0}\" between index 4 and the end is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in a section of the ArrayList.
myIndex = myAL.IndexOf( myString, 6, 6 );
Console.WriteLine( "The first occurrence of \"{0}\" between index 6 and index 11 is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in a small section at the end of the ArrayList.
myIndex = myAL.IndexOf( myString, 11 );
Console.WriteLine( "The first occurrence of \"{0}\" between index 11 and the end is at index {1}.", myString, myIndex );
}
public static void PrintIndexAndValues(IEnumerable myList)
{
int i = 0;
foreach (Object obj in myList)
Console.WriteLine(" [{0}]: {1}", i++, obj);
Console.WriteLine();
}
}
/*
This code produces output similar to the following:
The ArrayList contains the following values:
[0]: the
[1]: quick
[2]: brown
[3]: fox
[4]: jumps
[5]: over
[6]: the
[7]: lazy
[8]: dog
[9]: in
[10]: the
[11]: barn
The first occurrence of "the" is at index 0.
The first occurrence of "the" between index 4 and the end is at index 6.
The first occurrence of "the" between index 6 and index 11 is at index 6.
The first occurrence of "the" between index 11 and the end is at index -1.
*/
Imports System.Collections
Public Class SamplesArrayList
Public Shared Sub Main()
' Creates and initializes a new ArrayList with three elements of the same value.
Dim myAL As New ArrayList()
myAL.Add("the")
myAL.Add("quick")
myAL.Add("brown")
myAL.Add("fox")
myAL.Add("jumps")
myAL.Add("over")
myAL.Add("the")
myAL.Add("lazy")
myAL.Add("dog")
myAL.Add("in")
myAL.Add("the")
myAL.Add("barn")
' Displays the values of the ArrayList.
Console.WriteLine("The ArrayList contains the following values:")
PrintIndexAndValues(myAL)
' Search for the first occurrence of the duplicated value.
Dim myString As [String] = "the"
Dim myIndex As Integer = myAL.IndexOf(myString)
Console.WriteLine("The first occurrence of ""{0}"" is at index {1}.", myString, myIndex)
' Search for the first occurrence of the duplicated value in the last section of the ArrayList.
myIndex = myAL.IndexOf(myString, 4)
Console.WriteLine("The first occurrence of ""{0}"" between index 4 and the end is at index {1}.", myString, myIndex)
' Search for the first occurrence of the duplicated value in a section of the ArrayList.
myIndex = myAL.IndexOf(myString, 6, 6)
Console.WriteLine("The first occurrence of ""{0}"" between index 6 and index 11 is at index {1}.", myString, myIndex)
' Search for the first occurrence of the duplicated value in a small section at the end of the ArrayList.
myIndex = myAL.IndexOf(myString, 11)
Console.WriteLine("The first occurrence of ""{0}"" between index 11 and the end is at index {1}.", myString, myIndex)
End Sub
Public Shared Sub PrintIndexAndValues(ByVal myList As IEnumerable)
Dim i As Integer
Dim obj As [Object]
For Each obj In myList
Console.WriteLine(" [{0}]: {1}", i, obj)
i = i + 1
Next obj
Console.WriteLine()
End Sub
End Class
' This code produces the following output.
'
' The ArrayList contains the following values:
' [0]: the
' [1]: quick
' [2]: brown
' [3]: fox
' [4]: jumps
' [5]: over
' [6]: the
' [7]: lazy
' [8]: dog
' [9]: in
' [10]: the
' [11]: barn
'
' The first occurrence of "the" is at index 0.
' The first occurrence of "the" between index 4 and the end is at index 6.
' The first occurrence of "the" between index 6 and index 11 is at index 6.
' The first occurrence of "the" between index 11 and the end is at index -1.
'
Hinweise
Die ArrayList wird nach vorne gesucht, beginnend beim ersten Element und endend beim letzten Element.
Diese Methode führt eine lineare Suche aus. Daher ist diese Methode ein O(n) Vorgang, wobei n ist Count.
Diese Methode bestimmt die Gleichheit, indem aufgerufen Object.Equalswird.
Ab dem .NET Framework 2.0 verwendet diese Methode die -Objekte Equals und CompareTo -Methoden item der Auflistung, um zu bestimmen, ob ein Element vorhanden ist. In den früheren Versionen des .NET Framework wurde diese Bestimmung mithilfe der Equals Methoden und CompareTo des item Parameters für die Objekte in der Auflistung vorgenommen.
Weitere Informationen
- LastIndexOf(Object)
- Contains(Object)
- Durchführen kulturunabhängiger Zeichenfolgenoperationen in Auflistungen
Gilt für:
IndexOf(Object, Int32)
- Quelle:
- ArrayList.cs
- Quelle:
- ArrayList.cs
- Quelle:
- ArrayList.cs
public:
virtual int IndexOf(System::Object ^ value, int startIndex);public virtual int IndexOf (object value, int startIndex);public virtual int IndexOf (object? value, int startIndex);abstract member IndexOf : obj * int -> int
override this.IndexOf : obj * int -> intPublic Overridable Function IndexOf (value As Object, startIndex As Integer) As IntegerParameter
- startIndex
- Int32
Der nullbasierte Startindex für die Suche. 0 (null) ist in einer leeren Liste gültig.
Gibt zurück
Der nullbasierte Index des ersten Vorkommens von value innerhalb des Bereichs von Elementen in ArrayList, der sich von startIndex bis zum letzten Element erstreckt, sofern gefunden; andernfalls –1.
Ausnahmen
startIndex liegt außerhalb des Bereichs der gültigen Indizes für das ArrayList.
Beispiele
Im folgenden Codebeispiel wird gezeigt, wie der Index des ersten Vorkommens eines angegebenen Elements bestimmt wird.
using namespace System;
using namespace System::Collections;
void PrintIndexAndValues( IEnumerable^ myList );
int main()
{
// Creates and initializes a new ArrayList with three elements of the same value.
ArrayList^ myAL = gcnew ArrayList;
myAL->Add( "the" );
myAL->Add( "quick" );
myAL->Add( "brown" );
myAL->Add( "fox" );
myAL->Add( "jumps" );
myAL->Add( "over" );
myAL->Add( "the" );
myAL->Add( "lazy" );
myAL->Add( "dog" );
myAL->Add( "in" );
myAL->Add( "the" );
myAL->Add( "barn" );
// Displays the values of the ArrayList.
Console::WriteLine( "The ArrayList contains the following values:" );
PrintIndexAndValues( myAL );
// Search for the first occurrence of the duplicated value.
String^ myString = "the";
int myIndex = myAL->IndexOf( myString );
Console::WriteLine( "The first occurrence of \"{0}\" is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in the last section of the ArrayList.
myIndex = myAL->IndexOf( myString, 4 );
Console::WriteLine( "The first occurrence of \"{0}\" between index 4 and the end is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in a section of the ArrayList.
myIndex = myAL->IndexOf( myString, 6, 6 );
Console::WriteLine( "The first occurrence of \"{0}\" between index 6 and index 11 is at index {1}.", myString, myIndex );
}
void PrintIndexAndValues( IEnumerable^ myList )
{
int i = 0;
IEnumerator^ myEnum = myList->GetEnumerator();
while ( myEnum->MoveNext() )
{
Object^ obj = safe_cast<Object^>(myEnum->Current);
Console::WriteLine( " [{0}]: {1}", i++, obj );
}
Console::WriteLine();
}
/*
This code produces the following output.
The ArrayList contains the following values:
[0]: the
[1]: quick
[2]: brown
[3]: fox
[4]: jumps
[5]: over
[6]: the
[7]: lazy
[8]: dog
[9]: in
[10]: the
[11]: barn
The first occurrence of "the" is at index 0.
The first occurrence of "the" between index 4 and the end is at index 6.
The first occurrence of "the" between index 6 and index 11 is at index 6.
*/
using System;
using System.Collections;
public class SamplesArrayList
{
public static void Main()
{
// Creates and initializes a new ArrayList with three elements of the same value.
ArrayList myAL = new ArrayList();
myAL.Add( "the" );
myAL.Add( "quick" );
myAL.Add( "brown" );
myAL.Add( "fox" );
myAL.Add( "jumps" );
myAL.Add( "over" );
myAL.Add( "the" );
myAL.Add( "lazy" );
myAL.Add( "dog" );
myAL.Add( "in" );
myAL.Add( "the" );
myAL.Add( "barn" );
// Displays the values of the ArrayList.
Console.WriteLine( "The ArrayList contains the following values:" );
PrintIndexAndValues( myAL );
// Search for the first occurrence of the duplicated value.
string myString = "the";
int myIndex = myAL.IndexOf( myString );
Console.WriteLine( "The first occurrence of \"{0}\" is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in the last section of the ArrayList.
myIndex = myAL.IndexOf( myString, 4 );
Console.WriteLine( "The first occurrence of \"{0}\" between index 4 and the end is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in a section of the ArrayList.
myIndex = myAL.IndexOf( myString, 6, 6 );
Console.WriteLine( "The first occurrence of \"{0}\" between index 6 and index 11 is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in a small section at the end of the ArrayList.
myIndex = myAL.IndexOf( myString, 11 );
Console.WriteLine( "The first occurrence of \"{0}\" between index 11 and the end is at index {1}.", myString, myIndex );
}
public static void PrintIndexAndValues(IEnumerable myList)
{
int i = 0;
foreach (Object obj in myList)
Console.WriteLine(" [{0}]: {1}", i++, obj);
Console.WriteLine();
}
}
/*
This code produces output similar to the following:
The ArrayList contains the following values:
[0]: the
[1]: quick
[2]: brown
[3]: fox
[4]: jumps
[5]: over
[6]: the
[7]: lazy
[8]: dog
[9]: in
[10]: the
[11]: barn
The first occurrence of "the" is at index 0.
The first occurrence of "the" between index 4 and the end is at index 6.
The first occurrence of "the" between index 6 and index 11 is at index 6.
The first occurrence of "the" between index 11 and the end is at index -1.
*/
Imports System.Collections
Public Class SamplesArrayList
Public Shared Sub Main()
' Creates and initializes a new ArrayList with three elements of the same value.
Dim myAL As New ArrayList()
myAL.Add("the")
myAL.Add("quick")
myAL.Add("brown")
myAL.Add("fox")
myAL.Add("jumps")
myAL.Add("over")
myAL.Add("the")
myAL.Add("lazy")
myAL.Add("dog")
myAL.Add("in")
myAL.Add("the")
myAL.Add("barn")
' Displays the values of the ArrayList.
Console.WriteLine("The ArrayList contains the following values:")
PrintIndexAndValues(myAL)
' Search for the first occurrence of the duplicated value.
Dim myString As [String] = "the"
Dim myIndex As Integer = myAL.IndexOf(myString)
Console.WriteLine("The first occurrence of ""{0}"" is at index {1}.", myString, myIndex)
' Search for the first occurrence of the duplicated value in the last section of the ArrayList.
myIndex = myAL.IndexOf(myString, 4)
Console.WriteLine("The first occurrence of ""{0}"" between index 4 and the end is at index {1}.", myString, myIndex)
' Search for the first occurrence of the duplicated value in a section of the ArrayList.
myIndex = myAL.IndexOf(myString, 6, 6)
Console.WriteLine("The first occurrence of ""{0}"" between index 6 and index 11 is at index {1}.", myString, myIndex)
' Search for the first occurrence of the duplicated value in a small section at the end of the ArrayList.
myIndex = myAL.IndexOf(myString, 11)
Console.WriteLine("The first occurrence of ""{0}"" between index 11 and the end is at index {1}.", myString, myIndex)
End Sub
Public Shared Sub PrintIndexAndValues(ByVal myList As IEnumerable)
Dim i As Integer
Dim obj As [Object]
For Each obj In myList
Console.WriteLine(" [{0}]: {1}", i, obj)
i = i + 1
Next obj
Console.WriteLine()
End Sub
End Class
' This code produces the following output.
'
' The ArrayList contains the following values:
' [0]: the
' [1]: quick
' [2]: brown
' [3]: fox
' [4]: jumps
' [5]: over
' [6]: the
' [7]: lazy
' [8]: dog
' [9]: in
' [10]: the
' [11]: barn
'
' The first occurrence of "the" is at index 0.
' The first occurrence of "the" between index 4 and the end is at index 6.
' The first occurrence of "the" between index 6 and index 11 is at index 6.
' The first occurrence of "the" between index 11 and the end is at index -1.
'
Hinweise
Die ArrayList wird nach vorne gesucht, beginnend am startIndex letzten Element und endend.
Diese Methode führt eine lineare Suche aus. Daher ist diese Methode ein O(n) Vorgang, wobei n die Anzahl der Elemente von startIndex bis zum Ende des ArrayListist.
Diese Methode bestimmt die Gleichheit, indem aufgerufen Object.Equalswird.
Ab dem .NET Framework 2.0 verwendet diese Methode die -Objekte Equals und CompareTo -Methoden item der Auflistung, um zu bestimmen, ob ein Element vorhanden ist. In den früheren Versionen des .NET Framework wurde diese Bestimmung mithilfe der Equals Methoden und CompareTo des item Parameters für die Objekte in der Auflistung vorgenommen.
Weitere Informationen
- LastIndexOf(Object)
- Contains(Object)
- Durchführen kulturunabhängiger Zeichenfolgenoperationen in Auflistungen
Gilt für:
IndexOf(Object, Int32, Int32)
- Quelle:
- ArrayList.cs
- Quelle:
- ArrayList.cs
- Quelle:
- ArrayList.cs
public:
virtual int IndexOf(System::Object ^ value, int startIndex, int count);public virtual int IndexOf (object value, int startIndex, int count);public virtual int IndexOf (object? value, int startIndex, int count);abstract member IndexOf : obj * int * int -> int
override this.IndexOf : obj * int * int -> intPublic Overridable Function IndexOf (value As Object, startIndex As Integer, count As Integer) As IntegerParameter
- startIndex
- Int32
Der nullbasierte Startindex für die Suche. 0 (null) ist in einer leeren Liste gültig.
- count
- Int32
Die Anzahl der Elemente im zu durchsuchenden Abschnitt.
Gibt zurück
Der nullbasierte Index des ersten Vorkommens von value innerhalb des Bereichs von Elementen in ArrayList, der am startIndex beginnt und eine Anzahl von Elementen count enthält, sofern gefunden; andernfalls –1.
Ausnahmen
startIndex liegt außerhalb des Bereichs der gültigen Indizes für das ArrayList.
- oder -
count ist kleiner als Null.
- oder -
startIndex und count geben keinen gültigen Abschnitt in der ArrayList an.
Beispiele
Im folgenden Codebeispiel wird gezeigt, wie der Index des ersten Vorkommens eines angegebenen Elements bestimmt wird.
using namespace System;
using namespace System::Collections;
void PrintIndexAndValues( IEnumerable^ myList );
int main()
{
// Creates and initializes a new ArrayList with three elements of the same value.
ArrayList^ myAL = gcnew ArrayList;
myAL->Add( "the" );
myAL->Add( "quick" );
myAL->Add( "brown" );
myAL->Add( "fox" );
myAL->Add( "jumps" );
myAL->Add( "over" );
myAL->Add( "the" );
myAL->Add( "lazy" );
myAL->Add( "dog" );
myAL->Add( "in" );
myAL->Add( "the" );
myAL->Add( "barn" );
// Displays the values of the ArrayList.
Console::WriteLine( "The ArrayList contains the following values:" );
PrintIndexAndValues( myAL );
// Search for the first occurrence of the duplicated value.
String^ myString = "the";
int myIndex = myAL->IndexOf( myString );
Console::WriteLine( "The first occurrence of \"{0}\" is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in the last section of the ArrayList.
myIndex = myAL->IndexOf( myString, 4 );
Console::WriteLine( "The first occurrence of \"{0}\" between index 4 and the end is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in a section of the ArrayList.
myIndex = myAL->IndexOf( myString, 6, 6 );
Console::WriteLine( "The first occurrence of \"{0}\" between index 6 and index 11 is at index {1}.", myString, myIndex );
}
void PrintIndexAndValues( IEnumerable^ myList )
{
int i = 0;
IEnumerator^ myEnum = myList->GetEnumerator();
while ( myEnum->MoveNext() )
{
Object^ obj = safe_cast<Object^>(myEnum->Current);
Console::WriteLine( " [{0}]: {1}", i++, obj );
}
Console::WriteLine();
}
/*
This code produces the following output.
The ArrayList contains the following values:
[0]: the
[1]: quick
[2]: brown
[3]: fox
[4]: jumps
[5]: over
[6]: the
[7]: lazy
[8]: dog
[9]: in
[10]: the
[11]: barn
The first occurrence of "the" is at index 0.
The first occurrence of "the" between index 4 and the end is at index 6.
The first occurrence of "the" between index 6 and index 11 is at index 6.
*/
using System;
using System.Collections;
public class SamplesArrayList
{
public static void Main()
{
// Creates and initializes a new ArrayList with three elements of the same value.
ArrayList myAL = new ArrayList();
myAL.Add( "the" );
myAL.Add( "quick" );
myAL.Add( "brown" );
myAL.Add( "fox" );
myAL.Add( "jumps" );
myAL.Add( "over" );
myAL.Add( "the" );
myAL.Add( "lazy" );
myAL.Add( "dog" );
myAL.Add( "in" );
myAL.Add( "the" );
myAL.Add( "barn" );
// Displays the values of the ArrayList.
Console.WriteLine( "The ArrayList contains the following values:" );
PrintIndexAndValues( myAL );
// Search for the first occurrence of the duplicated value.
string myString = "the";
int myIndex = myAL.IndexOf( myString );
Console.WriteLine( "The first occurrence of \"{0}\" is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in the last section of the ArrayList.
myIndex = myAL.IndexOf( myString, 4 );
Console.WriteLine( "The first occurrence of \"{0}\" between index 4 and the end is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in a section of the ArrayList.
myIndex = myAL.IndexOf( myString, 6, 6 );
Console.WriteLine( "The first occurrence of \"{0}\" between index 6 and index 11 is at index {1}.", myString, myIndex );
// Search for the first occurrence of the duplicated value in a small section at the end of the ArrayList.
myIndex = myAL.IndexOf( myString, 11 );
Console.WriteLine( "The first occurrence of \"{0}\" between index 11 and the end is at index {1}.", myString, myIndex );
}
public static void PrintIndexAndValues(IEnumerable myList)
{
int i = 0;
foreach (Object obj in myList)
Console.WriteLine(" [{0}]: {1}", i++, obj);
Console.WriteLine();
}
}
/*
This code produces output similar to the following:
The ArrayList contains the following values:
[0]: the
[1]: quick
[2]: brown
[3]: fox
[4]: jumps
[5]: over
[6]: the
[7]: lazy
[8]: dog
[9]: in
[10]: the
[11]: barn
The first occurrence of "the" is at index 0.
The first occurrence of "the" between index 4 and the end is at index 6.
The first occurrence of "the" between index 6 and index 11 is at index 6.
The first occurrence of "the" between index 11 and the end is at index -1.
*/
Imports System.Collections
Public Class SamplesArrayList
Public Shared Sub Main()
' Creates and initializes a new ArrayList with three elements of the same value.
Dim myAL As New ArrayList()
myAL.Add("the")
myAL.Add("quick")
myAL.Add("brown")
myAL.Add("fox")
myAL.Add("jumps")
myAL.Add("over")
myAL.Add("the")
myAL.Add("lazy")
myAL.Add("dog")
myAL.Add("in")
myAL.Add("the")
myAL.Add("barn")
' Displays the values of the ArrayList.
Console.WriteLine("The ArrayList contains the following values:")
PrintIndexAndValues(myAL)
' Search for the first occurrence of the duplicated value.
Dim myString As [String] = "the"
Dim myIndex As Integer = myAL.IndexOf(myString)
Console.WriteLine("The first occurrence of ""{0}"" is at index {1}.", myString, myIndex)
' Search for the first occurrence of the duplicated value in the last section of the ArrayList.
myIndex = myAL.IndexOf(myString, 4)
Console.WriteLine("The first occurrence of ""{0}"" between index 4 and the end is at index {1}.", myString, myIndex)
' Search for the first occurrence of the duplicated value in a section of the ArrayList.
myIndex = myAL.IndexOf(myString, 6, 6)
Console.WriteLine("The first occurrence of ""{0}"" between index 6 and index 11 is at index {1}.", myString, myIndex)
' Search for the first occurrence of the duplicated value in a small section at the end of the ArrayList.
myIndex = myAL.IndexOf(myString, 11)
Console.WriteLine("The first occurrence of ""{0}"" between index 11 and the end is at index {1}.", myString, myIndex)
End Sub
Public Shared Sub PrintIndexAndValues(ByVal myList As IEnumerable)
Dim i As Integer
Dim obj As [Object]
For Each obj In myList
Console.WriteLine(" [{0}]: {1}", i, obj)
i = i + 1
Next obj
Console.WriteLine()
End Sub
End Class
' This code produces the following output.
'
' The ArrayList contains the following values:
' [0]: the
' [1]: quick
' [2]: brown
' [3]: fox
' [4]: jumps
' [5]: over
' [6]: the
' [7]: lazy
' [8]: dog
' [9]: in
' [10]: the
' [11]: barn
'
' The first occurrence of "the" is at index 0.
' The first occurrence of "the" between index 4 and the end is at index 6.
' The first occurrence of "the" between index 6 and index 11 is at index 6.
' The first occurrence of "the" between index 11 and the end is at index -1.
'
Hinweise
Die ArrayList wird vorwärts gesucht, beginnend bei startIndex und endet bei startIndex plus count minus 1, wenn count größer als 0 ist.
Diese Methode führt eine lineare Suche aus. Daher ist diese Methode ein O(n) Vorgang, wobei n ist count.
Diese Methode bestimmt die Gleichheit, indem aufgerufen Object.Equalswird.
Ab dem .NET Framework 2.0 verwendet diese Methode die -Objekte Equals und CompareTo -Methoden item der Auflistung, um zu bestimmen, ob ein Element vorhanden ist. In den früheren Versionen des .NET Framework wurde diese Bestimmung mithilfe der Equals Methoden und CompareTo des item Parameters für die Objekte in der Auflistung vorgenommen.
Weitere Informationen
- LastIndexOf(Object)
- Contains(Object)
- Durchführen kulturunabhängiger Zeichenfolgenoperationen in Auflistungen
Gilt für:
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