Question

我正在使用Entity Framework并尝试调用存储过程，但ExecuteSqlCommandAsync正在抛出未处理的异常。我已经把try / catch但是代码没有进入catch块。 ExecuteSqlCommand方法运行正常。

我得到的例外是

System.NullReferenceException＆＃39;发生在mscorlib.dll

我的代码：

try
{
    var inboundsParam = new SqlParameter();
    inboundsParam.ParameterName = "@Inbounds";
    inboundsParam.SqlDbType = SqlDbType.Xml;
    inboundsParam.Direction = ParameterDirection.Input;
    inboundsParam.Value = inboundsXml;

    var incomeFoundOutParam = new SqlParameter();
    incomeFoundOutParam.ParameterName = "@IncomeFound";
    incomeFoundOutParam.SqlDbType = SqlDbType.Bit;
    incomeFoundOutParam.Direction = ParameterDirection.Output;

    var output = await dbContext.Database.ExecuteSqlCommandAsync("EXEC dbo.CalculateIncome @Inbounds, @IncomeFound OUTPUT", inboundsParam, incomeFoundOutParam);
    var incomeFound = (bool)incomeFoundOutParam.Value;
}
catch(System.Exception ex)
{
}

有谁知道代码可能出现什么问题？

Answer 1

通过使用ExecuteSqlCommandAsync（），代码在另一个线程中运行，并且异常不在您的控制范围内。可以在AppDomain.CurrentDomain.UnhandledException事件处理程序中全局处理未处理的异常。该异常处理程序只是防止应用程序崩溃，而不能用于解决您的问题。仅供参考。

要解决您的问题，请使用另一种方法，创建自己的异步任务，以便您可以完全控制异常。并将您的异步呼叫替换为相应的同步呼叫。

public async void YourMethodAsync()
{
    // NOTE HERE TO CREATE YOUR OWN TASK, SO THAT YOU HAVE CONTROL TO THE EXCEPTION
    Task.Run(()=>{
        try
        {
            var inboundsParam = new SqlParameter();
            inboundsParam.ParameterName = "@Inbounds";
            inboundsParam.SqlDbType = SqlDbType.Xml;
            inboundsParam.Direction = ParameterDirection.Input;
            inboundsParam.Value = inboundsXml;

            var incomeFoundOutParam = new SqlParameter();
            incomeFoundOutParam.ParameterName = "@IncomeFound";
            incomeFoundOutParam.SqlDbType = SqlDbType.Bit;
            incomeFoundOutParam.Direction = ParameterDirection.Output;

            // NOTE HERE, USE SYNC METHOD CALL.
            var output = dbContext.Database.ExecuteSqlCommand("EXEC dbo.CalculateIncome @Inbounds, @IncomeFound OUTPUT", inboundsParam, incomeFoundOutParam);
            var incomeFound = (bool)incomeFoundOutParam.Value;
        }
        catch(System.Exception ex)
        {
        } 
    });
}

ExecuteSqlCommandAsync引发异常

1 个答案: