Enumerable.Reverse<TSource>(IEnumerable<TSource>) Method

Definition

反轉序列中項目的排序方向。Inverts the order of the elements in a sequence.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static System::Collections::Generic::IEnumerable<TSource> ^ Reverse(System::Collections::Generic::IEnumerable<TSource> ^ source);
public static System.Collections.Generic.IEnumerable<TSource> Reverse<TSource> (this System.Collections.Generic.IEnumerable<TSource> source);
static member Reverse : seq<'Source> -> seq<'Source>
<Extension()>
Public Function Reverse(Of TSource) (source As IEnumerable(Of TSource)) As IEnumerable(Of TSource)

Type Parameters

TSource

source 項目的類型。The type of the elements of source.

Parameters

source
IEnumerable<TSource>

要反轉方向的值序列。A sequence of values to reverse.

Returns

IEnumerable<TSource>

其項目對應於輸入序列中反向排序之項目的序列。A sequence whose elements correspond to those of the input sequence in reverse order.

Exceptions

sourcenullsource is null.

Examples

下列程式碼範例示範如何使用 Reverse 來反轉陣列中元素的順序。The following code example demonstrates how to use Reverse to reverse the order of elements in an array.

char[] apple = { 'a', 'p', 'p', 'l', 'e' };

char[] reversed = apple.Reverse().ToArray();

foreach (char chr in reversed)
{
    Console.Write(chr + " ");
}
Console.WriteLine();

/*
 This code produces the following output:

 e l p p a
*/
' Create a List of Char values.
Dim appleLetters As New List(Of Char)(New Char() _
                                  {"a"c, "P"c, "P"c, "L"c, "E"c})

' Reverse the order of the elements in the list.
' (We have to call AsEnumerable() in order to
' use System.Linq.Enumerable's Reverse() method.
Dim reversed() As Char =
appleLetters.AsEnumerable().Reverse().ToArray()

Dim output As New System.Text.StringBuilder
For Each chr As Char In reversed
    output.Append(chr & " ")
Next

' Display the output.
Console.WriteLine(output.ToString())

' This code produces the following output:
'
' E L P P a

Remarks

這個方法是使用延後執行來執行。This method is implemented by using deferred execution. 立即傳回值是一個物件,它會儲存執行動作所需的所有資訊。The immediate return value is an object that stores all the information that is required to perform the action. 在列舉物件之前,不會執行此方法所代表的查詢,方法是直接呼叫其 GetEnumerator 方法,或是在 Visual Basic 中C#使用 Visual 或 For Each 中的 foreachThe query represented by this method is not executed until the object is enumerated either by calling its GetEnumerator method directly or by using foreach in Visual C# or For Each in Visual Basic.

不同于 OrderBy,這個排序方法不會考慮實際值本身來決定順序。Unlike OrderBy, this sorting method does not consider the actual values themselves in determining the order. 相反地,它只會以相反順序傳回基礎來源產生的元素。Rather, it just returns the elements in the reverse order from which they are produced by the underlying source.

Applies to