在调用委托之前，将我的null检查代码显示为灰色 [英] Greyed out my codes of null checking before invoking a delegate

问题描述

我在VS 2015中编写了统一代码，这意味着它在c#4中，并且空条件运算符不可用.

I write unity codes in VS 2015, which means it's in c#4 and the null condition operator is not available.

在调用委托之前，我进行了空检查.但是，代码为灰色.这是否意味着格雷码不像注释一样有效?如果是这样，我应该怎么做才能防止调用空委托?

Before invoking a delegate, I did a null check. However the codes are greyed out. Does it mean the grey codes are not effective just like comments? If so what should I do to prevent invoking a null delegate?

public delegate void PtjAnimCtrlDelegateColiderSetEnabledTo(bool value);
public PjtAnimCtrlDelegateColliderSetEnabledTo colliderSetEnabledToHandler;

public delegate void PjtAnimCtrlDelegate();
public PjtAnimCtrlDelegate explosionAnimationFinishedHandler;
public PjtAnimCtrlDelegate hitTargetHandler;

public void ExplosionAnimationFinished()
{
  //pjtCtrl.ExplosionAnimationFinished();
  explosionAnimationFinishedHandler();
}

public void SetColliderEnabled()
{
  colliderSEtEnabledToHandler(true);
}

public void SetColliderDisabled() 
{
  colliderSetEnabledToHandler(false);
}

public void HitTarget()
{
  // this IF statement is gray in Visual Studio
  if (hitTargetHandler != null)
  { 
    hitTargetHandler();
  }
}

推荐答案

在调用委托之前，我进行了空检查.但是，代码为灰色.这是否意味着格雷码不像注释一样有效?

Before invoking a delegate, I did a null check. However the codes are greyed out. Does it mean the grey codes are not effective just like comments?

这意味着Visual Studio预编译器/设计时编译器检测到很有可能不需要该语句.

It means that the Visual Studio pre-compiler/design-time-compiler detects the statement is most likely not needed.

如果是的话，我应该怎么做才能防止调用空委托?

If so what should I do to prevent invoking a null delegate?

没什么，编译器仍然会在编译时(以及实际上也在运行时)确定是否需要该语句.

Nothing, the compiler will still determine at compile time (and actually at run-time as well) if the statement is needed.

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