DbRawSqlQuery<TElement>.ToDictionaryAsync<TKey, TResult> 方法 (Func<TElement, TKey>, Func<TElement, TResult>, IEqualityComparer<TKey>, CancellationToken)
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根據指定的索引鍵選取器函式、比較子和項目選取器函式，透過列舉以非同步方式從查詢建立 Dictionary<TKey, TValue>。
命名空間： System.Data.Entity.Infrastructure
組件： EntityFramework (在 EntityFramework.dll 中)
語法
'宣告
<SuppressMessageAttribute("Microsoft.Design", "CA1006:DoNotNestGenericTypesInMemberSignatures")> _
Public Function ToDictionaryAsync(Of TKey, TResult) ( _
keySelector As Func(Of TElement, TKey), _
elementSelector As Func(Of TElement, TResult), _
comparer As IEqualityComparer(Of TKey), _
cancellationToken As CancellationToken _
) As Task(Of Dictionary(Of TKey, TResult))
'用途
Dim instance As DbRawSqlQuery
Dim keySelector As Func(Of TElement, TKey)
Dim elementSelector As Func(Of TElement, TResult)
Dim comparer As IEqualityComparer(Of TKey)
Dim cancellationToken As CancellationToken
Dim returnValue As Task(Of Dictionary(Of TKey, TResult))
returnValue = instance.ToDictionaryAsync(keySelector, _
elementSelector, comparer, cancellationToken)
[SuppressMessageAttribute("Microsoft.Design", "CA1006:DoNotNestGenericTypesInMemberSignatures")]
public Task<Dictionary<TKey, TResult>> ToDictionaryAsync<TKey, TResult>(
Func<TElement, TKey> keySelector,
Func<TElement, TResult> elementSelector,
IEqualityComparer<TKey> comparer,
CancellationToken cancellationToken
)
[SuppressMessageAttribute(L"Microsoft.Design", L"CA1006:DoNotNestGenericTypesInMemberSignatures")]
public:
generic<typename TKey, typename TResult>
Task<Dictionary<TKey, TResult>^>^ ToDictionaryAsync(
Func<TElement, TKey>^ keySelector,
Func<TElement, TResult>^ elementSelector,
IEqualityComparer<TKey>^ comparer,
CancellationToken cancellationToken
)
[<SuppressMessageAttribute("Microsoft.Design", "CA1006:DoNotNestGenericTypesInMemberSignatures")>]
member ToDictionaryAsync :
keySelector:Func<'TElement, 'TKey> *
elementSelector:Func<'TElement, 'TResult> *
comparer:IEqualityComparer<'TKey> *
cancellationToken:CancellationToken -> Task<Dictionary<'TKey, 'TResult>>
JScript does not support generic types and methods.
類型參數
- TKey
由 keySelector 傳回之索引鍵的類型。
- TResult
elementSelector.
參數
- keySelector
類型：System.Func<TElement, TKey>
用來從各個項目擷取索引鍵的函式。
- elementSelector
類型：System.Func<TElement, TResult>
用來從每個項目產生結果項目值的轉換函式。
- comparer
類型：System.Collections.Generic.IEqualityComparer<TKey>
用來比較索引鍵的 IEqualityComparer<T>。
- cancellationToken
類型：System.Threading.CancellationToken
等候工作完成時要觀察的 CancellationToken。
傳回值
類型：System.Threading.Tasks.Task<Dictionary<TKey, TResult>>
表示非同步作業的工作。工作結果包含 Dictionary<TKey, TValue>，其包含從輸入序列中選取的類型 TResult 的值。
備註
不支援相同內容執行個體上的多個作用中作業。 使用 'await' 確保在此內容上呼叫另一個方法之前，所有非同步作業都已完成。