SortedList.ContainsValue(Object) Methode
Definitie
Belangrijk
Bepaalde informatie heeft betrekking op een voorlopige productversie die aanzienlijk kan worden gewijzigd voordat deze wordt uitgebracht. Microsoft biedt geen enkele expliciete of impliciete garanties met betrekking tot de informatie die hier wordt verstrekt.
Bepaalt of een SortedList object een specifieke waarde bevat.
public:
virtual bool ContainsValue(System::Object ^ value);
public virtual bool ContainsValue(object value);
abstract member ContainsValue : obj -> bool
override this.ContainsValue : obj -> bool
Public Overridable Function ContainsValue (value As Object) As Boolean
Parameters
- value
- Object
De waarde die in het SortedList object moet worden gevonden. De waarde kan zijn null.
Retouren
trueals het SortedList object een element bevat met de opgegeven value; anders . false
Voorbeelden
In het volgende codevoorbeeld ziet u hoe u kunt bepalen of een SortedList object een specifiek element bevat.
using System;
using System.Collections;
public class SamplesSortedList {
public static void Main() {
// Creates and initializes a new SortedList.
SortedList mySL = new SortedList();
mySL.Add( 2, "two" );
mySL.Add( 4, "four" );
mySL.Add( 1, "one" );
mySL.Add( 3, "three" );
mySL.Add( 0, "zero" );
// Displays the values of the SortedList.
Console.WriteLine( "The SortedList contains the following values:" );
PrintIndexAndKeysAndValues( mySL );
// Searches for a specific key.
int myKey = 2;
Console.WriteLine( "The key \"{0}\" is {1}.", myKey, mySL.ContainsKey( myKey ) ? "in the SortedList" : "NOT in the SortedList" );
myKey = 6;
Console.WriteLine( "The key \"{0}\" is {1}.", myKey, mySL.ContainsKey( myKey ) ? "in the SortedList" : "NOT in the SortedList" );
// Searches for a specific value.
string myValue = "three";
Console.WriteLine( "The value \"{0}\" is {1}.", myValue, mySL.ContainsValue( myValue ) ? "in the SortedList" : "NOT in the SortedList" );
myValue = "nine";
Console.WriteLine( "The value \"{0}\" is {1}.", myValue, mySL.ContainsValue( myValue ) ? "in the SortedList" : "NOT in the SortedList" );
}
public static void PrintIndexAndKeysAndValues( SortedList myList ) {
Console.WriteLine( "\t-INDEX-\t-KEY-\t-VALUE-" );
for ( int i = 0; i < myList.Count; i++ ) {
Console.WriteLine( "\t[{0}]:\t{1}\t{2}", i, myList.GetKey(i), myList.GetByIndex(i) );
}
Console.WriteLine();
}
}
/*
This code produces the following output.
The SortedList contains the following values:
-INDEX- -KEY- -VALUE-
[0]: 0 zero
[1]: 1 one
[2]: 2 two
[3]: 3 three
[4]: 4 four
The key "2" is in the SortedList.
The key "6" is NOT in the SortedList.
The value "three" is in the SortedList.
The value "nine" is NOT in the SortedList.
*/
Imports System.Collections
Public Class SamplesSortedList
Public Shared Sub Main()
' Creates and initializes a new SortedList.
Dim mySL As New SortedList()
mySL.Add(2, "two")
mySL.Add(4, "four")
mySL.Add(1, "one")
mySL.Add(3, "three")
mySL.Add(0, "zero")
' Displays the values of the SortedList.
Console.WriteLine("The SortedList contains the following values:")
PrintIndexAndKeysAndValues(mySL)
' Searches for a specific key.
Dim myKey As Integer = 2
Dim msg As String
If mySL.ContainsKey(myKey) Then
msg = "in the SortedList"
Else
msg = "NOT in the SortedList"
End If
Console.WriteLine("The key ""{0}"" is {1}.", myKey, msg)
myKey = 6
If mySL.ContainsKey(myKey) Then
msg = "in the SortedList"
Else
msg = "NOT in the SortedList"
End If
Console.WriteLine("The key ""{0}"" is {1}.", myKey, msg)
' Searches for a specific value.
Dim myValue As String = "three"
If mySL.ContainsValue(myValue) Then
msg = "in the SortedList"
Else
msg = "NOT in the SortedList"
End If
Console.WriteLine("The value ""{0}"" is {1}.", myValue, msg)
myValue = "nine"
If mySL.ContainsValue(myValue) Then
msg = "in the SortedList"
Else
msg = "NOT in the SortedList"
End If
Console.WriteLine("The value ""{0}"" is {1}.", myValue, msg)
End Sub
Public Shared Sub PrintIndexAndKeysAndValues(myList As SortedList)
Console.WriteLine(ControlChars.Tab & "-INDEX-" & ControlChars.Tab & _
"-KEY-" & ControlChars.Tab & "-VALUE-")
Dim i As Integer
For i = 0 To myList.Count - 1
Console.WriteLine(ControlChars.Tab & "[{0}]:" & ControlChars.Tab & _
"{1}" & ControlChars.Tab & "{2}", i, myList.GetKey(i), _
myList.GetByIndex(i))
Next i
Console.WriteLine()
End Sub
End Class
' This code produces the following output.
'
' The SortedList contains the following values:
' -INDEX- -KEY- -VALUE-
' [0]: 0 zero
' [1]: 1 one
' [2]: 2 two
' [3]: 3 three
' [4]: 4 four
'
' The key "2" is in the SortedList.
' The key "6" is NOT in the SortedList.
' The value "three" is in the SortedList.
' The value "nine" is NOT in the SortedList.
Opmerkingen
De waarden van de elementen van het SortedList object worden vergeleken met de opgegeven waarde met behulp van de Equals methode.
Met deze methode wordt een lineaire zoekopdracht uitgevoerd; daarom is de gemiddelde uitvoeringstijd evenredig met Count. Dat wil gezegd, deze methode is een O(n) bewerking, waar n is Count.
Deze methode maakt gebruik van de objecten Equals en CompareTo methoden item van de verzameling om te bepalen of item deze bestaat.