Question

我在代码审查中遇到了以下方法。在循环内部，Resharper告诉我if (narrativefound == false)是不正确的，因为narrativeFound始终为真。我不认为是这种情况，因为为了将narrativeFound设置为true，它必须首先传递条件字符串比较，那么它怎么总是真的呢？我错过了什么吗？这是Resharper或我们的代码中的错误吗？

public Chassis GetChassisForElcomp(SPPA.Domain.ChassisData.Chassis asMaintained, SPPA.Domain.ChassisData.Chassis newChassis)
{
    Chassis c = asMaintained;
    List<Narrative> newNarrativeList = new List<Narrative>();

    foreach (Narrative newNarrative in newChassis.Narratives)
    {
         bool narrativefound = false; 

         foreach (Narrative orig in asMaintained.Narratives)
         {
                if (string.Compare(orig.PCode, newNarrative.PCode) ==0 )
                {
                          narrativefound = true;
                          if (newNarrative.NarrativeValue.Trim().Length != 0)
                          {
                             orig.NarrativeValue = newNarrative.NarrativeValue;
                             newNarrativeList.Add(orig);                            
                          }
                          break;
                }
                if (narrativefound == false)
                {
                     newNarrativeList.Add(newNarrative); 
                }
         }
    }

    c.SalesCodes = newChassis.SalesCodes;
    c.Narratives = newNarrativeList;
    return c; 
}

Answer 1

当控制到达该语句时，变量narrativefound永远不会为真：

narrativefound = true;
// ...
break;  // This causes control to break out of the loop.

我认为Resharper试图告诉你条件narrativefound == false将永远是真的。

Answer 2

您根本不需要narrativeFound变量。在您将其设置为true的范围内，您将从foreach循环中断。如果您未将其设置为true，则不会中断，并将newNarrative添加到newNarrativeList。

所以，这可以改写为

foreach (Narrative newNarrative in newChassis.Narratives)
{
     foreach (Narrative orig in asMaintained.Narratives)
     {
            if (string.Compare(orig.PCode, newNarrative.PCode) == 0)
            {
                      if (newNarrative.NarrativeValue.Trim().Length != 0)
                      {
                         orig.NarrativeValue = newNarrative.NarrativeValue;
                         newNarrativeList.Add(orig);                            
                      }
                      break;
            }

            newNarrativeList.Add(newNarrative);                 
     }
}

Answer 3

这是您代码中的错误。

foreach (Narrative newNarrative in newChassis.Narratives) 
{ 
     bool narrativefound = false;  

     foreach (Narrative orig in asMaintained.Narratives) 
     { 
            if (string.Compare(orig.PCode, newNarrative.PCode) ==0 ) 
            { 
                      narrativefound = true; 
                      if (newNarrative.NarrativeValue.Trim().Length != 0) 
                      { 
                         orig.NarrativeValue = newNarrative.NarrativeValue; 
                         newNarrativeList.Add(orig);                             
                      } 
// narrativeFound == true, but now we exit the for loop
                      break; 
            } 
// narrativeFound is always false here.  The test is redundant
            if (narrativefound == false) 
            { 
                 newNarrativeList.Add(newNarrative);  
            } 
     } 
}

Answer 4

R＃是正确的，因为如果你将narrativefound变为true，那么你在设置之后就会突然脱离foreach。

Answer 5

我相信它告诉你，如果将narriativefound设置为true，则退出for循环（break;）。因此，如果if（narriativefound == false）被评估，它将始终具有false值。

此代码段中是否存在无法访问的代码？我不这么认为，但是Resharper却告诉我了

5 个答案: