Java initialize list with same value

• Reference

Namespace: System.Collections Assemblies:mscorlib.dll, System.Collections.NonGeneric.dll Assembly:System.Runtime.dll Assembly:System.Collections.NonGeneric.dll Assembly:System.Runtime.Extensions.dll Assembly:mscorlib.dll Assembly:netstandard.dll

Important

Some information relates to prerelease product that may be substantially modified before its released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

public: static System::Collections::ArrayList ^ Repeat[System::Object ^ value, int count]; public static System.Collections.ArrayList Repeat [object value, int count]; public static System.Collections.ArrayList Repeat [object? value, int count]; static member Repeat : obj * int -> System.Collections.ArrayList Public Shared Function Repeat [value As Object, count As Integer] As ArrayList

Parameters

Returns

ArrayList

An ArrayList with count number of elements, all of which are copies of value.

Exceptions

Examples

The following code example shows how to create and initialize a new ArrayList with the same value.

using namespace System; using namespace System::Collections; void PrintValues[ IEnumerable^ myList ]; int main[] { // Creates a new ArrayList with five elements and initialize each element with a null value. ArrayList^ myAL = ArrayList::Repeat[ 0, 5 ]; // Displays the count, capacity and values of the ArrayList. Console::WriteLine[ "ArrayList with five elements with a null value" ]; Console::WriteLine[ " Count : {0}", myAL->Count ]; Console::WriteLine[ " Capacity : {0}", myAL->Capacity ]; Console::Write[ " Values:" ]; PrintValues[ myAL ]; // Creates a new ArrayList with seven elements and initialize each element with the string "abc". myAL = ArrayList::Repeat[ "abc", 7 ]; // Displays the count, capacity and values of the ArrayList. Console::WriteLine[ "ArrayList with seven elements with a string value" ]; Console::WriteLine[ " Count : {0}", myAL->Count ]; Console::WriteLine[ " Capacity : {0}", myAL->Capacity ]; Console::Write[ " Values:" ]; PrintValues[ myAL ]; } void PrintValues[ IEnumerable^ myList ] { IEnumerator^ myEnum = myList->GetEnumerator[]; while [ myEnum->MoveNext[] ] { Object^ obj = safe_cast[myEnum->Current]; Console::Write[ " {0}", obj ]; } Console::WriteLine[]; } /* This code produces the following output. ArrayList with five elements with a null value Count : 5 Capacity : 16 Values: ArrayList with seven elements with a string value Count : 7 Capacity : 16 Values: abc abc abc abc abc abc abc */ using System; using System.Collections; public class SamplesArrayList { public static void Main[] { // Creates a new ArrayList with five elements and initialize each element with a null value. ArrayList myAL = ArrayList.Repeat[ null, 5 ]; // Displays the count, capacity and values of the ArrayList. Console.WriteLine[ "ArrayList with five elements with a null value" ]; Console.WriteLine[ " Count : {0}", myAL.Count ]; Console.WriteLine[ " Capacity : {0}", myAL.Capacity ]; Console.Write[ " Values:" ]; PrintValues[ myAL ]; // Creates a new ArrayList with seven elements and initialize each element with the string "abc". myAL = ArrayList.Repeat[ "abc", 7 ]; // Displays the count, capacity and values of the ArrayList. Console.WriteLine[ "ArrayList with seven elements with a string value" ]; Console.WriteLine[ " Count : {0}", myAL.Count ]; Console.WriteLine[ " Capacity : {0}", myAL.Capacity ]; Console.Write[ " Values:" ]; PrintValues[ myAL ]; } public static void PrintValues[ IEnumerable myList ] { foreach [ Object obj in myList ] Console.Write[ " {0}", obj ]; Console.WriteLine[]; } } /* This code produces the following output. ArrayList with five elements with a null value Count : 5 Capacity : 16 Values: ArrayList with seven elements with a string value Count : 7 Capacity : 16 Values: abc abc abc abc abc abc abc */ Imports System.Collections Public Class SamplesArrayList Public Shared Sub Main[] ' Creates a new ArrayList with five elements and initialize each ' element with a null value. Dim myAL As ArrayList = ArrayList.Repeat[Nothing, 5] ' Displays the count, capacity and values of the ArrayList. Console.WriteLine["ArrayList with five elements with a null value"] Console.WriteLine[" Count : {0}", myAL.Count] Console.WriteLine[" Capacity : {0}", myAL.Capacity] Console.Write[" Values:"] PrintValues[myAL] ' Creates a new ArrayList with seven elements and initialize each ' element with the string "abc". myAL = ArrayList.Repeat["abc", 7] ' Displays the count, capacity and values of the ArrayList. Console.WriteLine["ArrayList with seven elements with a string value"] Console.WriteLine[" Count : {0}", myAL.Count] Console.WriteLine[" Capacity : {0}", myAL.Capacity] Console.Write[" Values:"] PrintValues[myAL] End Sub Public Shared Sub PrintValues[myList As IEnumerable] Dim obj As [Object] For Each obj In myList Console.Write[" {0}", obj] Next obj Console.WriteLine[] End Sub End Class ' This code produces the following output. ' ' ArrayList with five elements with a null value ' Count : 5 ' Capacity : 16 ' Values: ' ArrayList with seven elements with a string value ' Count : 7 ' Capacity : 16 ' Values: abc abc abc abc abc abc abc

Remarks

ArrayList accepts null as a valid value and allows duplicate elements.

This method is an O[n] operation, where n is count.

Applies to

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