DbRawSqlQuery<TElement>.ToDictionaryAsync<TKey, TResult> 方法 (Func<TElement, TKey>, Func<TElement, TResult>, IEqualityComparer<TKey>)
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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) _
) 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 returnValue As Task(Of Dictionary(Of TKey, TResult))
returnValue = instance.ToDictionaryAsync(keySelector, _
elementSelector, comparer)
[SuppressMessageAttribute("Microsoft.Design", "CA1006:DoNotNestGenericTypesInMemberSignatures")]
public Task<Dictionary<TKey, TResult>> ToDictionaryAsync<TKey, TResult>(
Func<TElement, TKey> keySelector,
Func<TElement, TResult> elementSelector,
IEqualityComparer<TKey> comparer
)
[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
)
[<SuppressMessageAttribute("Microsoft.Design", "CA1006:DoNotNestGenericTypesInMemberSignatures")>]
member ToDictionaryAsync :
keySelector:Func<'TElement, 'TKey> *
elementSelector:Func<'TElement, 'TResult> *
comparer:IEqualityComparer<'TKey> -> 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>。
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。