发表新帖
发表新帖

Implementing python slice notation

前端 未结
关注
6 570
轻奢々
轻奢々 2021-02-07 05:06

I\'m trying to reimplement python slice notation in another language (php) and looking for a snippet (in any language or pseudocode) that would mimic the python logic. That is,

6条回答
  • 故里飘歌
    故里飘歌 (楼主)
    2021-02-07 06:01

    This is a solution I came up with in C# .NET, maybe not the prettiest, but it works.

    private object[] Slice(object[] list, int start = 0, int stop = 0, int step = 0)
{
    List result = new List();

    if (step == 0) step = 1;
    if (start < 0)
    {
        for (int i = list.Length + start; i < list.Length - (list.Length + start); i++)
        {
            result.Add(list[i]);
        }
    }
    if (start >= 0 && stop == 0) stop = list.Length - (start >= 0 ? start : 0);
    else if (start >= 0 && stop < 0) stop = list.Length + stop;

    int loopStart = (start < 0 ? 0 : start);
    int loopEnd = (start > 0 ? start + stop : stop);

    if (step > 0)
    {
        for (int i = loopStart; i < loopEnd; i += step)
            result.Add(list[i]);
    }
    else if (step < 0)
    {
        for (int i = loopEnd - 1; i >= loopStart; i += step)
            result.Add(list[i]);
    }

    return result.ToArray();
}

    
    
             
    
                                                        
    
            
            
    
              
                
                0
              
                   
                
               讨论(0)
              
                                                  
              
              
    
                          
             
       
          
              
    
                                       
    

    

                
    
                         
          
                              			
        
        
        
    
          
    
            
            
    
              
              
    
            
    


                                 
              
    
            
    
                          
    

        
         
    
                
                
    
                  
                
    
                
    
                   看不清?
                
    
              
    
                                  
    
                    
   
                 
             
              
    提交回复
    
            
    
          
    
        
    
      
       
      
    
    
    
          
 
     
 
    
        
    热议问题