如何通过LINQ中的另一个成员选择每个旋转字符串和组

Question

如何与linq中的其他成员选择许多拆分字符串？

class LogData
{
  public string IndexPattern {get; set;}
  public string Version {get;set;}
  public string Type1 {get; set;}
  public string Type2 {get; set;}
  //here has a constructor of this class
}

我有一个日志数据列表，这些数据具有许多日志基准。索引模式是使用定界符"，"的日志索引集。

List<LogData> logList = new List<LogData>();
logList.add(new LogData("1,2,4", "Ver1", "pro" , "etc" ) );
logList.add(new LogData("1", "Ver2", "pro" , "etc" ) );
logList.add(new LogData("2", "Ver1", "pro" , "etc" ) );
logList.add(new LogData("1,2,4", "Ver1", "pro" , "etc" ) );
logList.add(new LogData("1,5", "Ver2", "pro" , "set" ) );

我想要这样的分组索引模式和组。

[Index] [Version] [Type1] [Type2] [Count]
  1        Ver1     pro      etc    2
  2        Ver1     pro      etc    2
  4        Ver2     pro      etc    2
  1        Ver2     pro      etc    1
  1        Ver2     pro      set    1
  5        Ver2     pro      set    1
  4        Ver2     pro      set    1

，我先写下这样的linq。

var LogGroup = HackingLogs.GroupBy(g => new {
              IndexPattern = g.IndexPattern.SelectMany( new { Index = c => c 
               }),  //I must select many to get each splited  string
                g.Version,
                g.Type1,
                g.Type2
 }); //I group by this for each splited string and all member pairs to select 

，但不能分组。因此我无法使用SELECT。我可以解决这个问题吗？

Answer 1

您可以首先使用SelectMany和Project所有其他元素来板 IndexPattern。最后，按所有列分组并获得计数。这应该给您预期的输出： -

 var res = logList.SelectMany(x => x.IndexPattern.Split(',')
                                  .Select(z => new 
                                      { 
                                           Index = z, 
                                           Version = x.Version, 
                                           Type1 = x.Type1, 
                                           Type2 = x.Type2 
                                      }))
                   .GroupBy(x => new { x.Index, x.Version, x.Type1, x.Type2 })
                   .Select(x => new
                        {
                            Index = x.Key.Index,
                            Version = x.Key.Version,
                            Type1 = x.Key.Type1,
                            Type2 = x.Key.Type2,
                            Count = x.Count()
                        });

工作小提琴。

Answer 2

今天，我学到了linq 的魔法。这是不使用Linq

的代码

我发现这个问题很有趣，所以只会发布我的尝试。

using System;
using System.Collections.Generic;
public class Program
{
    public class LogData
    {
      public string IndexPattern {get; set;}
      public string Version {get;set;}
      public string Type1 {get; set;}
      public string Type2 {get; set;}
      //here has a constructor of LogData class
        public LogData(string indexPattern, string version, string type1, string type2){
            IndexPattern = indexPattern;
            Version = version;
            Type1 = type1;
            Type2 = type2;
        }
    }
    public class GridData
    {
      public string Index {get; set;}
      public string Version {get;set;}
      public string Type1 {get; set;}
      public string Type2 {get; set;}
        public int count {get;set;}
      //here has a constructor of GridData class
        public GridData(string indexPattern, string version, string type1, string type2, int count){
            Index = indexPattern;
            Version = version;
            Type1 = type1;
            Type2 = type2;
            this.count = count;
        }
    }
    public static void Main(){
        //Inputs
        List<LogData> logList = new List<LogData>();
        logList.Add(new LogData("1,2,4", "Ver1", "pro" , "etc" ) );
        logList.Add(new LogData("1", "Ver2", "pro" , "etc" ) );
        logList.Add(new LogData("2", "Ver1", "pro" , "etc" ) );
        logList.Add(new LogData("1,2,4", "Ver1", "pro" , "etc" ) );
        logList.Add(new LogData("1,5", "Ver2", "pro" , "set" ) );
        //Calculate the results
        Dictionary<string, GridData> result = GetResult(logList);
        Display(result);
    }
    //Read all data and Get result in tabular format
    public static Dictionary<string, GridData> GetResult(List<LogData> logList){
        //Initialization of local variable
        List<LogData> elements = new List<LogData>();
        Dictionary<string, GridData> output = new Dictionary<string, GridData>();
        //Iterate through each input
        foreach(LogData ld in logList){
            LogData temp = new LogData("", "", "", "");
            //Check for multiple Indexs in one list
            if(ld.IndexPattern.Contains(",")){
                string[] strArr = ld.IndexPattern.Split(',');
                //Consider each index as one record; Time complexity: O(n*m) very bad
                foreach(string s1 in strArr){
                    temp = new LogData(s1, ld.Version, ld.Type1, ld.Type2);
                    elements.Add(temp);
                }
            }
                //Else record as it is
            else{
                elements.Add(ld);
            }
        }
            //List elements contains all seperated records
            foreach(LogData logData in elements){
                //Create unique key by concatenating all properties into string
                string key = logData.IndexPattern + "_" +  logData.Version +"_"+ logData.Type1 +"_"+logData.Type2;
                //Increment counter if record is already exist
                if(output.ContainsKey(key))
                    output[key].count++;
                else{
                    //Insert new record
                    GridData gd = new GridData(logData.IndexPattern, logData.Version, logData.Type1, logData.Type2, 1);
                    output.Add(key, gd);
                }
    }
        return output;
    }
    //Display in tabular format
    public static void Display(Dictionary<string, GridData> output){
        foreach(string str in output.Keys){
            Console.WriteLine(output[str].Index +"t"+ output[str].Version +"t"+ output[str].Type1 +"t"+ output[str].Type2 +"t"+ output[str].count);
        }
    }
}

改进得到赞赏。dotnetfiddler