共用方式為

IDbCommandInterceptor.ReaderExecutingAsync 方法

  • 參考

定義

命名空間:
Microsoft.EntityFrameworkCore.Diagnostics
組件:
Microsoft.EntityFrameworkCore.Relational.dll
套件:
Microsoft.EntityFrameworkCore.Relational v3.0.0
套件:
Microsoft.EntityFrameworkCore.Relational v3.1.0
套件:
Microsoft.EntityFrameworkCore.Relational v5.0.0
套件:
Microsoft.EntityFrameworkCore.Relational v6.0.0
套件:
Microsoft.EntityFrameworkCore.Relational v7.0.0
套件:
Microsoft.EntityFrameworkCore.Relational v8.0.0

在 EF 想要呼叫 之前呼叫 ExecuteReaderAsync() 。

public System.Threading.Tasks.Task<Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader>> ReaderExecutingAsync (System.Data.Common.DbCommand command, Microsoft.EntityFrameworkCore.Diagnostics.CommandEventData eventData, Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader> result, System.Threading.CancellationToken cancellationToken = default);
public System.Threading.Tasks.ValueTask<Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader>> ReaderExecutingAsync (System.Data.Common.DbCommand command, Microsoft.EntityFrameworkCore.Diagnostics.CommandEventData eventData, Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader> result, System.Threading.CancellationToken cancellationToken = default);
public virtual System.Threading.Tasks.ValueTask<Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader>> ReaderExecutingAsync (System.Data.Common.DbCommand command, Microsoft.EntityFrameworkCore.Diagnostics.CommandEventData eventData, Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader> result, System.Threading.CancellationToken cancellationToken = default);
abstract member ReaderExecutingAsync : System.Data.Common.DbCommand * Microsoft.EntityFrameworkCore.Diagnostics.CommandEventData * Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader> * System.Threading.CancellationToken -> System.Threading.Tasks.Task<Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader>>
abstract member ReaderExecutingAsync : System.Data.Common.DbCommand * Microsoft.EntityFrameworkCore.Diagnostics.CommandEventData * Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader>>
abstract member ReaderExecutingAsync : System.Data.Common.DbCommand * Microsoft.EntityFrameworkCore.Diagnostics.CommandEventData * Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader>>
override this.ReaderExecutingAsync : System.Data.Common.DbCommand * Microsoft.EntityFrameworkCore.Diagnostics.CommandEventData * Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<Microsoft.EntityFrameworkCore.Diagnostics.InterceptionResult<System.Data.Common.DbDataReader>>
Public Function ReaderExecutingAsync (command As DbCommand, eventData As CommandEventData, result As InterceptionResult(Of DbDataReader), Optional cancellationToken As CancellationToken = Nothing) As Task(Of InterceptionResult(Of DbDataReader))
Public Function ReaderExecutingAsync (command As DbCommand, eventData As CommandEventData, result As InterceptionResult(Of DbDataReader), Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of InterceptionResult(Of DbDataReader))
Public Overridable Function ReaderExecutingAsync (command As DbCommand, eventData As CommandEventData, result As InterceptionResult(Of DbDataReader), Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of InterceptionResult(Of DbDataReader))

參數

command
DbCommand

命令。

eventData
CommandEventData

命令和執行的相關內容資訊。

result
InterceptionResult<DbDataReader>

如果存在，則表示目前的結果。 如果某些先前的攔截器藉由呼叫 SuppressWithResult(TResult) 來隱藏執行，這個值將會 HasResult 設定為 true 。 這個值通常用來做為這個方法實作的傳回值。

cancellationToken
CancellationToken

CancellationToken等候工作完成時要觀察的 。

傳回

Task<InterceptionResult<DbDataReader>>
ValueTask<InterceptionResult<DbDataReader>>

如果 HasResult 為 false，EF 會如常繼續。 如果 HasResult 為 true，EF 將會隱藏即將執行的作業，並改為使用 Result 。 任何未嘗試變更結果的攔截器實作這個方法，就是傳回 result 傳入的值，通常使用 FromResult<TResult>(TResult)

例外狀況

OperationCanceledException

如果取消 CancellationToken。

適用於