用“as bool”?“而不是”object something=viewstate[”hi“]”

所以我在看旧代码(2.0),我发现了:

object isReviewingValue = ViewState["IsReviewing"];

if (isReviewingValue is bool)
{
  return (bool)isReviewingValue;
}

我的第一个想法是用“as”关键字来避免不需要的

(bool)isReviewingValue;

但是“as”只适用于非值类型。没问题,我就这么做了:

bool? isReviewingValue= ViewState["IsReviewing"] as bool?;
if (isReviewingValue.HasValue)
{
  return isReviewingValue.Value;
}

问题是:除了看起来更易读之外,这真的更好吗?

编辑:

public Stopwatch AsRun()
{
  Stopwatch watch = new Stopwatch();

  watch.Start();
  for (Int32 loopCounter = 0; loopCounter < 10000; loopCounter++)
  {
    Object value = true;
    Boolean? test = value as Boolean?;
    if (test.HasValue)
    {
      Boolean something = test.Value;
    }
  }
  watch.Stop();

  return watch;
}

public Stopwatch ObjectIsRun()
{
  Stopwatch watch = new Stopwatch();

  watch.Start();
  for (Int32 loopCounter = 0; loopCounter < 10000; loopCounter++)
  {
    Object test = true;
    if (test is Boolean)
    {
      Boolean something = (Boolean)test;
    }
  }
  watch.Stop();

  return watch;
}

答案:结果是,使用上述方法以测试的方式运行时,原始代码的速度大约快10倍。