c# - 在 EF Core 2.0 中使用 DataTable 作为表值参数

Question

[更新问题描述]
我们有一个批量导入过程，我们正在通过 IEnumerable<SqlDataRecord>作为存储过程的表值参数 (TVP)，如 DataTable Type 在 EF Core 1.1 之前不可用。我们刚刚升级了我们的项目以使用 .Net Core 2.0，并开始更新代码以使用 DataTable。 ExecuteSqlCommandAsync 命令开始抛出 InvalidCastException .
以下是异常详情:

System.InvalidCastException occurred
  HResult=0x80004002
  Message=Failed to convert parameter value from a DataTable to a IEnumerable`1.
  Source=<Cannot evaluate the exception source>
  StackTrace:
   at System.Data.SqlClient.SqlParameter.CoerceValue(Object value, MetaType destinationType, Boolean& coercedToDataFeed, Boolean& typeChanged, Boolean allowStreaming)
   at System.Data.SqlClient.SqlParameter.GetCoercedValue()
   at System.Data.SqlClient.SqlParameter.Validate(Int32 index, Boolean isCommandProc)
   at System.Data.SqlClient.SqlCommand.BuildParamList(TdsParser parser, SqlParameterCollection parameters)
   at System.Data.SqlClient.SqlCommand.BuildExecuteSql(CommandBehavior behavior, String commandText, SqlParameterCollection parameters, _SqlRPC& rpc)
   at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async, Int32 timeout, Task& task, Boolean asyncWrite, SqlDataReader ds)
   at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, TaskCompletionSource`1 completion, Int32 timeout, Task& task, Boolean asyncWrite, String method)
   at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(TaskCompletionSource`1 completion, Boolean sendToPipe, Int32 timeout, Boolean asyncWrite, String methodName)
   at System.Data.SqlClient.SqlCommand.BeginExecuteNonQuery(AsyncCallback callback, Object stateObject)
   at System.Threading.Tasks.TaskFactory`1.FromAsyncImpl(Func`3 beginMethod, Func`2 endFunction, Action`1 endAction, Object state, TaskCreationOptions creationOptions)
   at System.Threading.Tasks.TaskFactory`1.FromAsync(Func`3 beginMethod, Func`2 endMethod, Object state)
   at System.Data.SqlClient.SqlCommand.ExecuteNonQueryAsync(CancellationToken cancellationToken)
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at Microsoft.EntityFrameworkCore.Storage.Internal.RelationalCommand.<ExecuteAsync>d__26.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at Microsoft.EntityFrameworkCore.RelationalDatabaseFacadeExtensions.<ExecuteSqlCommandAsync>d__11.MoveNext()
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at System.Runtime.CompilerServices.TaskAwaiter`1.GetResult()
   at X.Y.Repositories.Repository.<Import>d__4.MoveNext() in Repository.cs:line 95
   at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
   at System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
   at X.Y.Services.ImportService`2.<BulkImportAsync>d__6.MoveNext() in ImportService.cs:line 70

Inner Exception 1:
InvalidCastException: Object must implement IConvertible.

这就是我调用存储过程的方式:

var dataTable = new DataTable();
dataTable.Columns.Add("Col1", typeof(String));
dataTable.Columns.Add("Col2", typeof(String)); //and so on

foreach (var record in records)
{
    var row = dataTable.NewRow();
    SetStringValue(row, "Col1", record.Field1); //SetStringValue is just a helper method that assigns DBNull.Value if the field value is null. 
    SetStringValue(row, "Col2", record.Field2); //and so on

    dataTable.Rows.Add(row);
}

var param = new SqlParameter("@Records", dataTable)
{
    TypeName = "TVPRecords",
    SqlDbType = SqlDbType.Structured
};

await _dbContext.Database.ExecuteSqlCommandAsync("EXEC dbo.ImportData @Records", param);

与 DataTable现在在 EF Core 2.0 中可用，我仍然无法使用它作为 TVP 传递给存储过程。是因为它还不支持还是可能是一个错误？

Answer 1

我在你的代码中发现的唯一可能的错误是 SqlParameter的 TypeName .你的不是完全合格的，我需要包含模式，即“dbo。”。
我正在使用 EFCore 2.0.2 和 EFCore.SqlServer 2.0.2
这是我的代码:

DataTable table = new DataTable();
table.Columns.Add(new DataColumn("FieldId", typeof(int)));
table.Columns.Add(new DataColumn("Value", typeof(double)));
foreach (Value v in NewRows)
{
    DataRow row = table.NewRow();
    row["FieldId"] = v.FieldId;
    row["Value"] = v.Value;
    table.Rows.Add(row);
}

var param = new SqlParameter("@replacementValues", table) { TypeName = "dbo.CustomSqlType", SqlDbType = SqlDbType.Structured };
await _dbContext.Database.ExecuteSqlCommandAsync("EXEC dbo.UpdateValues @replacementValues", param);