在每个索引中对嵌套列表进行求和的值

Question

我有一个叫做_DataCollection的List<List<string>>，其中每个嵌套列表都有相同数量的值。虽然所有字符串都是嵌套列表中的值，但它们是由字母数字字符，空字符串或货币值组成的字符串。例如

_DataCollection[0] = {"tom", "abc", "$525.34", "$123"} 
_DataCollection[1] = {"dick", "xyz", "$100", "$234"} 
_DataCollection[2] = {"harry", "", "$250.01", "$40"} 
_DataCollection[2] = {"bob", "", "$250.01", ""} 

我需要做的就是拿出一个办法来总结每个索引的所有值在所有嵌套列表并且将其添加到列表什么：

newSumList[0] = "N/A" since "tom" + "dick" + "harry" + "bob" can't be aggregated. 
newSumList[1] = "N/A" since "abc" + "xyz" + "" + "" can't be aggregated. 
newSumList[2] = "1125.36" 
newSumList[3] = "397" even though the last value of the last nested list is "". 

基本上，总所有数字每个索引的嵌套列表中的值。

我能想到的唯一方法是迭代这些并保持运行总数，但我想知道是否可以使用LINQ或其他方法来完成这项工作。

Answer 1

你在这里。

var list = new List<List<string>> 
{ 
    new List<string> {"tom", "abc", "$525.34", "$123"}, 
    new List<string> {"dick", "xyz", "$100", "$234"}, 
    new List<string> {"harry", "", "$250.01", "$40"}, 
    new List<string> {"bob", "", "$250.01", ""} 
}; 

decimal num; 
var itemsPerLine = list[0].Count; // 4 
var res = list.SelectMany(line => line); 
       .Select((s, i) => new { Text = s, Index = i }) 
       .GroupBy(i => i.Index % itemsPerLine) // transformed matrix here 
       .Select(g => g.Sum(i => 
        decimal.TryParse(i.Text, NumberStyles.AllowCurrencySymbol | 
              NumberStyles.AllowDecimalPoint, 
              new CultureInfo("en-US"), out num) 
              ? num : 0)); 

当然，您可以通过更改NumberStyles标志和文化信息来指定应该识别为数字的内容。

Answer 2

List<List<string>> _DataCollection=new List<List<string>>(); 
      _DataCollection.Add(new List<string> {"tom", "abc", "$525.34", "$123"}); 

      _DataCollection.Add(new List<string> {"dick", "xyz", "$100", "$234"}); 
      _DataCollection.Add(new List<string> {"harry", "", "$250.01", "$40"}); 
      _DataCollection.Add(new List<string> {"bob", "", "$250.01", ""}); 

      List<string> newSumList = new List<string>(); 

      for (int i = 0; i < _DataCollection.Count; i++) 
      { 
       decimal Sum = 0; 
       string CurrentSumList; 
       string Comment; 
       decimal amount = 0; 
       for (int j = 0; j < _DataCollection.Count; j++) 
       { 
        bool IsDecimalAmount=decimal.TryParse(_DataCollection[j][i].Replace('$','0'),out amount); 
        if (IsDecimalAmount) 
        { 

         Sum += amount; 
        } 
        else 
        { 
         Comment = "String"; 

        } 
       } 
       CurrentSumList = Sum.ToString(); 
       newSumList.Add(CurrentSumList); 
      } 

我已经实施了这个&它给了我结果。

Answer 3

试试这个： -

decimal _temp =0; 
int ListLength = _DataCollection.First().Count(); 
      var query = _DataCollection.SelectMany(x => x). 
             Select((v, i) => new { Val = v, Index = i % ListLength }) 
             .GroupBy(x => x.Index) 
             .Select(z => z.Sum(y => decimal.TryParse(y.Val,out _temp) ? _temp : 0)); 

工作Fiddle。

Answer 4

// Replace $value with value and remove all non-value strings 
var dollars = _DataCollection 
    .Select(l => l.Select(str => str.Contains('$') ? str.Split('$')[1] : string.Empty)); 

var newSumList = new List<double>(); 

// Add all values in a new list 
for (int i = 0; i < _DataCollection[0].Count; i++) 
{ 
    double toAdd = 0; 
    foreach (var entry in dollars) 
    { 
     // If entry is a value, parse it, 0 otherwise 
     var value = entry.ElementAt(i) != string.Empty ? double.Parse(entry.ElementAt(i)) : 0; 
     toAdd = toAdd + value; 
    } 
    newSumList.Add(toAdd); 
} 
newSumList.ForEach(Console.WriteLine); 

Answer 5

或者，对于不同的方法，不需要与GroupBy重新排列顺序：

 var culture = new CultureInfo("en-US"); 
     List<string> sums = 
      _DataCollection.Count == 0 
      ? new List<string>() 
      : Enumerable.Range(0, _DataCollection.First().Count) 
      .Select(i => _DataCollection.Select(list => list[i]) 
         .Select(s => { decimal val; return string.IsNullOrEmpty(s) ? (decimal?)0 : decimal.TryParse(s, NumberStyles.Currency, culture, out val) ? (decimal?)val : (decimal?)null; }) 
         .Aggregate((decimal?)0, (sum, val) => sum + val)) 
      .Select(sum => sum.HasValue ? sum.Value.ToString(culture) : "N/A") 
      .ToList(); 

Answer 6

不反复多次，支持空源列表

var list = new List<string[]> 
{ 
    new [] {"tom", "abc", "$525.34", "$123"}, 
    new [] {"dick", "xyz", "$100", "$234"}, 
    new [] {"harry", "", "$250.01", "$40"}, 
    new [] {"bob", "", "$250.01", ""} 
}; 
var cutlure = new CultureInfo("en-US"); 
var result = list.Aggregate((decimal[])null, (sums, strings) => 
    { 
     if (sums == null) 
      sums = Enumerable.Repeat(decimal.MinValue, strings.Length).ToArray(); 
     for (int i = 0; i < strings.Length; i++) 
     { 
      decimal value; 
      if (decimal.TryParse(strings[i], NumberStyles.Currency, cutlure, out value)) 
       sums[i] = (sums[i] == decimal.MinValue) ? value : sums[i] + value; 
     } 
     return sums; 
    }, 
    sums => sums.Select(sum => (sum == decimal.MinValue) ? "N/A" : sum.ToString()).ToArray());