重构嵌套的 foreach 语句

Question

我有一个嵌套 foreach语句，它成功地完成了我想做的事情。唯一的问题是，它看起来很乱。如何重构代码以使其更具可读性和简洁性？List<int> dofm = new List<int>();var dayOfMonth = Convert.ToString(ut.dayOfMonth);dofm = dayOfMonth  .Split(',')  .Select(s => {     int.TryParse(s, out int i);     return i - 1; })  .ToList();foreach (var a in model.Schedule.DofMInfo){    foreach (var b in dofm)    {        if (a.DofMID.Equals(b))        {            a.IsChecked = true;        }    }}

Answer 1

您可以使用Join：

var items = model.Schedule.DofMInfo

    .Join(dofm, dmi => dmi.DofMID, d => d, (dmi, d) => dmi);

foreach (var item in items)

{

    item.IsChecked = true;

}

Answer 2

我建议这样的事情：

// HashSet is faster than List<T> on Contains: O(1) vs. O(N)

HashSet<int> dofm = new HashSet<int>(dayOfMonth

  .Split(',')

  .Select(s => int.TryParse(s, out int i) ? i - 1 : -1));

// Second loop can be changed into "Contains"

foreach(var a in model.Schedule.DofMInfo)

  if (dofm.Contains(a.DofMID))

    a.IsChecked = true;