Array.ConvertAll<TInput,TOutput>(TInput[], Converter<TInput,TOutput>) 方法

定义

将一种类型的数组转换为另一种类型的数组。Converts an array of one type to an array of another type.

public:
generic <typename TInput, typename TOutput>
 static cli::array <TOutput> ^ ConvertAll(cli::array <TInput> ^ array, Converter<TInput, TOutput> ^ converter);
public static TOutput[] ConvertAll<TInput,TOutput> (TInput[] array, Converter<TInput,TOutput> converter);
static member ConvertAll : 'Input[] * Converter<'Input, 'Output> -> 'Output[]
Public Shared Function ConvertAll(Of TInput, TOutput) (array As TInput(), converter As Converter(Of TInput, TOutput)) As TOutput()

类型参数

TInput

源数组元素的类型。The type of the elements of the source array.

TOutput

目标数组元素的类型。The type of the elements of the target array.

参数

array
TInput[]

要转换为目标类型的从零开始的一维 ArrayThe one-dimensional, zero-based Array to convert to a target type.

converter
Converter<TInput,TOutput>

用于将每个元素从一种类型转换为另一种类型的 Converter<TInput,TOutput>A Converter<TInput,TOutput> that converts each element from one type to another type.

返回

TOutput[]

目标类型的数组,包含从源数组转换而来的元素。An array of the target type containing the converted elements from the source array.

异常

arraynullarray is null.

- 或 --or- converternullconverter is null.

示例

下面的代码示例定义了一个名为 PointFToPoint 的方法,该方法将 PointF 结构转换为 Point 结构。The following code example defines a method named PointFToPoint that converts a PointF structure to a Point structure. 然后,该示例创建一个 PointF 结构的数组,创建一个 Converter<PointF, Point> 委托(在 Visual Basic 中为Converter(Of PointF, Point))以表示 PointFToPoint 方法,并将该委托传递给 ConvertAll 方法。The example then creates an array 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. ConvertAll 方法将输入列表的每个元素传递到 PointFToPoint 方法,并将转换后的元素放入 Point 结构的新列表中。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. 将显示这两个列表。Both lists are displayed.

#using <System.Drawing.dll>

using namespace System;
using namespace System::Drawing;
using namespace System::Collections::Generic;

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

void main()
{
    // Create an array of PointF objects.
    array<PointF>^ apf = {
        PointF(27.8F, 32.62F),
        PointF(99.3F, 147.273F),
        PointF(7.5F, 1412.2F) };


    // Display each element in the PointF array.
    Console::WriteLine();
    for each(PointF p in apf)
    {
        Console::WriteLine(p);
    }

    // Convert each PointF element to a Point object.
    array<Point>^ ap = 
        Array::ConvertAll(apf, 
            gcnew Converter<PointF, Point>(PointFToPoint)
        );

    // Display each element in the Point array.
    Console::WriteLine();
    for each(Point p in ap)
    {
        Console::WriteLine(p);
    }
}

/* 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}
 */
using System;
using System.Drawing;
using System.Collections.Generic;

public class Example
{
    public static void Main()
    {
        // Create an array of PointF objects.
        PointF[] apf = {
            new PointF(27.8F, 32.62F),
            new PointF(99.3F, 147.273F),
            new PointF(7.5F, 1412.2F) };

        // Display each element in the PointF array.
        Console.WriteLine();
        foreach( PointF p in apf )
            Console.WriteLine(p);

        // Convert each PointF element to a Point object.
        Point[] ap = Array.ConvertAll(apf, 
            new Converter<PointF, Point>(PointFToPoint));

        // Display each element in the Point array.
        Console.WriteLine();
        foreach( Point p in ap )
        {
            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}
 */
Imports System.Drawing
Imports System.Collections.Generic

Public Class Example
    Public Shared Sub Main()
        ' Create an array of PointF objects.
        Dim apf() As PointF = { _
            New PointF(27.8, 32.62), _
            New PointF(99.3, 147.273), _
            New PointF(7.5, 1412.2)  }

        ' Display each element in the PointF array.
        Console.WriteLine()
        For Each p As PointF In apf
            Console.WriteLine(p)
        Next
        
        ' Convert each PointF element to a Point object.
        Dim ap() As Point = Array.ConvertAll(apf, _
            New Converter(Of PointF, Point)(AddressOf PointFToPoint))

        ' Display each element in the Point array.
        Console.WriteLine()
        For Each p As Point In ap
            Console.WriteLine(p)
        Next
    End Sub

    Public Shared Function PointFToPoint(ByVal pf As PointF) _
        As Point

        Return New Point(CInt(pf.X), CInt(pf.Y))
    End Function
End Class
' The example produces the following output:
'       {X=27.8, Y=32.62}
'       {X=99.3, Y=147.273}
'       {X=7.5, Y=1412.2}
'       
'       {X=28,Y=33}
'       {X=99,Y=147}
'       {X=8,Y=1412}

注解

Converter<TInput,TOutput> 是对方法的委托,该方法将对象转换为目标类型。The Converter<TInput,TOutput> is a delegate to a method that converts an object to the target type. array 的元素分别传递到 Converter<TInput,TOutput>,转换后的元素保存在新数组中。The elements of array are individually passed to the Converter<TInput,TOutput>, and the converted elements are saved in the new array.

array 保持不变。The source array remains unchanged.

此方法是一个 O (n)操作,其中 narrayLengthThis method is an O(n) operation, where n is the Length of array.

适用于

另请参阅