发表新帖
发表新帖

Sorting a collection by multiple fields

后端 未结
关注
4 726
甜味超标
甜味超标 2020-12-21 07:17

I need to sort a collection. For example, I have

Austin 12/3/2012   
Sam 100 12/3/2012   
Sam 200 14/3/2012   
Bubly 300 12/3/2012   
Bubly 300 15/3/2012
4条回答
  • 情话喂你
    情话喂你 (楼主)
    2020-12-21 08:06

    First you create two functions:

    var SortByDate=(p=>p.Date);
var SortByName=(p=>p.Name);

    Then you have, for example, a List containing the two

    var SortDimensions=new List({SortByDate,SortByName});



    Then you if you want to sort by first date then name you do:
    


    myList.OrderBy(SortDimensions[0]).ThenBy(SortDimensions[1]);

    


    Now, here is the tricky part, if you want to sort by name first then date you just alter the order of the functions in the SortDimensionsList:
    


    SortDimensions.Remove(SortByName);
SortDimensions.Insert(0,SortByName);

    


    This way, the same OrderBy statement will give you a different result.
    


    PS. Admittedly, this is rather close to being pseudocode since you may have to use something other than List for the SortDimensions collection to avoid compiler errors, but I don't have access to an IDE at the moment, but the spirit of the answer remains the same. Create a collection, store delegate functions in it, then alter the order within the collection to achieve different sorting dimensions using the same generic code.
    
    
    
             
    
                                                        
    
            
            
    
              
                
                0
              
                   
                
               讨论(0)
              
                                                  
              
              
    
                          
             
       
          
              
    
                                       
    

    

                
    
                         
          
                              			
        
        
        
    
          
    
            
            
    
              
              
    
            
    


                                 
              
    
            
    
                          
    

        
         
    
                
                
    
                  
                
    
                
    
                   看不清?
                
    
              
    
                                  
    
                    
   
                 
             
              
    提交回复
    
            
    
          
    
        
    
      
       
      
    
    
    
          
 
     
 
    
        
    热议问题