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List.ConvertAll Generic Method

Converts the elements in the current List to another type, and returns a list containing the converted elements.

Namespace: System.Collections.Generic
Assembly: mscorlib (in mscorlib.dll)

public List<TOutput> ConvertAll<TOutput> (
	Converter<T,TOutput> converter
)
J# supports the use of generic types and methods, but not the declaration of new ones.
JScript does not support generic types and methods.
Not applicable.

Type Parameters

TOutput

The type of the elements of the target array.

Parameters

converter

A Converter delegate that converts each element from one type to another type.

Return Value

A List of the target type containing the converted elements from the current List.
Exception typeCondition

ArgumentNullException

converter is a null reference (Nothing in Visual Basic).

The Converter is a delegate to a method that converts an object to the target type. The elements of the current List are individually passed to the Converter delegate, and the converted elements are saved in the new List.

The current List remains unchanged.

This method is an O(n) operation, where n is Count.

The following code example defines a method named PointFToPoint that converts a PointF structure to a Point structure. The example then creates a List of PointF structures, creates a Converter<PointF, Point> delegate (Converter(Of PointF, Point) in Visual Basic) to represent the PointFToPoint method, and passes the delegate to the ConvertAll method. The ConvertAll method passes each element of the input list to the PointFToPoint method and puts the converted elements into a new list of Point structures. Both lists are displayed.

using System;
using System.Drawing;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        List<PointF> lpf = new List<PointF>();

        lpf.Add(new PointF(27.8F, 32.62F));
        lpf.Add(new PointF(99.3F, 147.273F));
        lpf.Add(new PointF(7.5F, 1412.2F));

        Console.WriteLine();
        foreach( PointF p in lpf )
        {
            Console.WriteLine(p);
        }

        List<Point> lp = lpf.ConvertAll( 
            new Converter<PointF, Point>(PointFToPoint));

        Console.WriteLine();
        foreach( Point p in lp )
        {
            Console.WriteLine(p);
        }
    }

    public static Point PointFToPoint(PointF pf)
    {
        return new Point(((int) pf.X), ((int) pf.Y));
    }
}

/* This code example produces the following output:

{X=27.8, Y=32.62}
{X=99.3, Y=147.273}
{X=7.5, Y=1412.2}

{X=27,Y=32}
{X=99,Y=147}
{X=7,Y=1412}
 */

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0, 2.0

.NET Compact Framework

Supported in: 2.0

XNA Framework

Supported in: 1.0
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