SortedList<TKey, TValue> Constructor (Int32)

Initializes a new instance of the SortedList<TKey, TValue> class that is empty, has the specified initial capacity, and uses the default IComparer<T>.

Namespace:  System.Collections.Generic
Assemblies:   System (in System.dll)
  System.Collections (in System.Collections.dll)

public SortedList(
	int capacity
)

Parameters

capacity
Type: System.Int32

The initial number of elements that the SortedList<TKey, TValue> can contain.

ExceptionCondition
ArgumentOutOfRangeException

capacity is less than zero.

Every key in a SortedList<TKey, TValue> must be unique according to the default comparer.

The capacity of a SortedList<TKey, TValue> is the number of elements that the SortedList<TKey, TValue> can hold before resizing. As elements are added to a SortedList<TKey, TValue>, the capacity is automatically increased as required by reallocating the internal array.

If the size of the collection can be estimated, specifying the initial capacity eliminates the need to perform a number of resizing operations while adding elements to the SortedList<TKey, TValue>.

The capacity can be decreased by calling TrimExcess or by setting the Capacity property explicitly. Decreasing the capacity reallocates memory and copies all the elements in the SortedList<TKey, TValue>.

This constructor uses the default comparer for TKey. To specify a comparer, use the SortedList<TKey, TValue>(Int32, IComparer<TKey>) constructor. The default comparer Comparer<T>.Default checks whether the key type TKey implements System.IComparable<T> and uses that implementation, if available. If not, Comparer<T>.Default checks whether the key type TKey implements System.IComparable. If the key type TKey does not implement either interface, you can specify a System.Collections.Generic.IComparer<T> implementation in a constructor overload that accepts a comparer parameter.

This constructor is an O(n) operation, where n is capacity.

The following code example creates a sorted list with an initial capacity of 4 and populates it with 4 entries.

using System;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        // Create a new sorted list of strings, with string keys and 
        // an initial capacity of 4.
        SortedList<string, string> openWith = 
                               new SortedList<string, string>(4);

        // Add 4 elements to the list. 
        openWith.Add("txt", "notepad.exe");
        openWith.Add("bmp", "paint.exe");
        openWith.Add("dib", "paint.exe");
        openWith.Add("rtf", "wordpad.exe");

        // List the contents of the sorted list.
        Console.WriteLine();
        foreach( KeyValuePair<string, string> kvp in openWith )
        {
            Console.WriteLine("Key = {0}, Value = {1}", 
               kvp.Key, kvp.Value);
        }
    }
}

/* This code example produces the following output:

Key = bmp, Value = paint.exe
Key = dib, Value = paint.exe
Key = rtf, Value = wordpad.exe
Key = txt, Value = notepad.exe
 */

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0
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