切换语句,突破for循环以重新切换到切换

时间:2013-03-28 16:17:14

标签: c

我在主循环中有一个开关,它将运行我的游戏。我试图打破我的开关,以便转到另一种情况。以下示例更好地解释了它:

int j = 0;
While(1){
switch(j){
case 0:  ....
        break;
case 1: 
      for( i =0; i > 100; i++){
       if(lives == 0)
        j = 2;
        break; //this is where I want to break out of my switch to go to case 2. But it         
               //breaks out of my for loop. I do not know how to get around this. Thank 
               //you!
       }
 case 2: //some stuff I want to do
}

}

8 个答案:

答案 0 :(得分:1)

如果您想要突破并直接进入案例2,那么您的代码应该完全正确。

答案 1 :(得分:1)

我想你只想在case 2时点击lives == 0。如果是这样,您需要将break;{ }放在j = 2;中 - 这样只会在lives == 0时打破循环。然后,如果您在break;末尾放置case 0,则会终止切换,然后由于while(1)重新进入切换,然后点击case 2:

你的for循环应该是for(i = 0; i < 100; i++)而不是for(i = 0; i > 100; i++)

int j = 0;
While(1){
  switch(j){
  case 0:  ....
    break;
  case 1: 
    for( i =0; i < 100; i++){
      if(lives == 0) {
        j = 2;
        break;
      }
    }
    break;
 case 2: //some stuff I want to do
  }
}

答案 2 :(得分:1)

好的,你实际上是在正确的轨道上,但是,如上所述,你需要检查你的循环条件。

int j = 0;
While(1){
switch(j){
case 0:  ....
    break;
case 1: 
  for( i =0; i < 100; i++){
    if(lives == 0){
        j = 2;
        break; // Break for
    }
  }
if(j != 2) break; // If no break in the switch's case, then continue to the next case
case 2: //some stuff I want to do
    break;
} //End Switch
} //End While

答案 3 :(得分:1)

构建这样的状态机:

C#     bool OnceMore = true;

string ProcessState = "Start"
while(OnceMore)
{
   OnceMore = False;
   switch(ProcessState)
   {
      case "Start" :
      {
     // do something
     ProcessState = "Check";
         OnceMore = True;
     break;
      }
      case "Check" :
      {
         // do check
         if( Check == "Ok")
         {
            ProcessState = "Close";
         }
         else // try again
         {
            ProcessState = "Start";
         }
         OnceMore = True;
         break;
      }
      case "Close" :
      {
         // do what you need to return to the caller
         break;
      }
   }
}
return

答案 4 :(得分:0)

你不能突破多个可破坏的范围,你只能突破最高的范围。

对此的草率“解决方案”是使用goto jump。

真正的解决方案是将您的功能分解为更小的逻辑一口大小的功能,然后您可以随意中断或返回。为了代码质量和清洁目的,你的for循环几乎肯定应该在它自己的功能中。

bool doSomethingInALoopWithADescriptiveName(int &var)
{
    for(int i = 0; i < 100; i++)
    {
        if(lives_WhichShouldntBeGlobal == 0)
        {
            var = 2;
            return false;
        }
    }

    return true;
}

void myFuncWithADescriptiveName()
{
    int variableWithADescriptiveName = 0;
    while(true)
    {
        switch(j)
        {
            case 0:
            {
                //....
            } break;
            case 1:
            {
                bool continueLooping = doSomethingInALoopWithADescriptiveName(&variableWithADescriptiveName);
                if(!continueLooping)
                {
                    return;
                }
            } break;
            case 2:
            {
                //some stuff I want to do
            } break;
        }
    }
}

注意:由于问题的标记问题,我不确定问题的语言是什么。我的答案适用于多种语言(可以概括为“编写简单,紧凑,自我描述和干净的代码”),但我的代码示例是伪C ++,但很容易适用于其他语言。

答案 5 :(得分:0)

switch(j){
case 0:  ....
    break test;
case 1: 
  for( i =0; i > 100; i++){
   if(lives == 0)
    j = 2;
    break; //this is where I want to break out of my switch to go to case 2. But it         
           //breaks out of my for loop. I do not know how to get around this. Thank 
           //you!
   }
break test;
case 2: //some stuff I want to do
 break test;
}


test://After switch.

答案 6 :(得分:0)

将大括号括在触发下一个案例的条件

case 1: 
   for( i =0; i > 100; i++)
   {
       if(lives == 0)
       {
           j = 2;
           break; // This exits the for effectively jumping at the case break

       }
       // I suppose here you have other code to process 
       // that should not be executed if (lives == 0)
   }
   break;

答案 7 :(得分:0)

你的休息时间突破了for循环。因此,您需要添加一些额外的逻辑来检查循环是否提前退出,然后再次调用break。

其次,对于(i = 0; i> 100; i ++)永远不会执行,因为我永远不会&gt; 100。

for(int i = 0; i < 100; i++)
{
    if(lives == 0)
    {
        j = 2;
        quit = true;
        break; //Break out of the loop
    }
}
//Note, if this language is C, control will just fall through to case 2 anyway.
//If C#, you have to add a break at the end of this case regardless
if(quit == true)
{
    break; //Break out of switch
}