c# - 对于 WinRT Metro Apps 什么等同于 Parallel.ForEach

Question

这是有关 Parallel.For 的 MSDN 页面中的示例代码。我想在 WinRT C# 中做同样的事情:

#region Sequential_Loop
static void MultiplyMatricesSequential(double[,] matA, double[,] matB, double[,] result)
{
    int matACols = matA.GetLength(1);
    int matBCols = matB.GetLength(1);
    int matARows = matA.GetLength(0);

    for (int i = 0; i < matARows; i++)
    {
        for (int j = 0; j < matBCols; j++)
        {
            for (int k = 0; k < matACols; k++)
            {
                result[i, j] += matA[i, k] * matB[k, j];
            }
        }
    }
}
#endregion

#region Parallel_Loop

static void MultiplyMatricesParallel(double[,] matA, double[,] matB, double[,] result)
{
    int matACols = matA.GetLength(1);
    int matBCols = matB.GetLength(1);
    int matARows = matA.GetLength(0);

    // A basic matrix multiplication.
    // Parallelize the outer loop to partition the source array by rows.
    Parallel.For(0, matARows, i =>
    {
        for (int j = 0; j < matBCols; j++)
        {
            // Use a temporary to improve parallel performance.
            double temp = 0;
            for (int k = 0; k < matACols; k++)
            {
                temp += matA[i, k] * matB[k, j];
            }
            result[i, j] = temp;
        }
    }); // Parallel.For
}

#endregion

WinRT Metro 的等效 int C# 是什么？

我应该创建一个任务数组并等待该数组完成吗？

Answer 1

Metro 应用程序不应该执行繁重的 CPU 密集型操作。我不确定应用商店的要求是什么，但如果您的应用在长时间内耗尽 CPU 资源而被拒绝，我不会感到惊讶。

也就是说，Metro 确实支持并行异步操作，您可以使用它来进行一些基本的并行处理(如果必须的话):

static async Task MultiplyMatricesAsync(double[,] matA, double[,] matB, double[,] result)
{
  int matACols = matA.GetLength(1);
  int matBCols = matB.GetLength(1);
  int matARows = matA.GetLength(0);

  var tasks = Enumerable.Range(0, matARows).Select(i =>
      Task.Run(() =>
      {
        for (int j = 0; j < matBCols; j++)
        {
          // Use a temporary to improve parallel performance.
          double temp = 0;
          for (int k = 0; k < matACols; k++)
          {
            temp += matA[i, k] * matB[k, j];
          }
          result[i, j] = temp;
        }
      }));
  await Task.WhenAll(tasks);
}