C# 过滤掉Linq中的空值
我有以下(工作)代码。它非常不雅观,我认为它可以仅使用Linq进行重构,从而避免C# 过滤掉Linq中的空值,c#,linq,C#,Linq,我有以下(工作)代码。它非常不雅观,我认为它可以仅使用Linq进行重构,从而避免foreach循环,并且必须依赖外部列表。如何做到这一点?谢谢 List<string> answerValues = new List<string>(); foreach (Fillings filling in fillings) { string answer = filling.Answers.Where(a => a.Questions == ques
foreach
循环,并且必须依赖外部列表。如何做到这一点?谢谢
List<string> answerValues = new List<string>();
foreach (Fillings filling in fillings)
{
string answer = filling.Answers.Where(a => a.Questions == question)
.Select(a => a.Answer).FirstOrDefault();
if (!string.IsNullOrEmpty(answer)) answerValues.Add(answer);
}
List answerValues=new List();
foreach(填充物填充物)
{
字符串答案=填充.答案.其中(a=>a.问题==问题)
.Select(a=>a.Answer).FirstOrDefault();
如果(!string.IsNullOrEmpty(answer))answerValues.Add(answer);
}
IEnumerable answerValues=填充
.选择多个(f=>f.答案)
.其中(a=>a.问题==问题)
.选择(a=>a.答案)
.Where(ans=>!string.IsNullOrEmpty(ans));
或者,如果您需要列表:
IList<string> answerValues = fillings
.SelectMany(f => f.Answers)
.Where(a => a.Questions == question)
.Select(a => a.Answer)
.Where(ans => !string.IsNullOrEmpty(ans))
.ToList();
IList answerValues=填充
.选择多个(f=>f.答案)
.其中(a=>a.问题==问题)
.选择(a=>a.答案)
.Where(ans=>!string.IsNullOrEmpty(ans))
.ToList();
IList<string> answerValues = fillings
.SelectMany(f => f.Answers)
.Where(a => a.Questions == question)
.Select(a => a.Answer)
.Where(ans => !string.IsNullOrEmpty(ans))
.ToList();
var answerValues = (
from f in fillings
from a in f.Answers
where a.Question == question
where !String.IsNullOrEmpty(a.Answer)
select a.Answer).ToList();
fillings.SelectMany(x => x.Answers.Where(a => a.Question == question)
.Select(a => a.Answer)
.FirstOrDefault())
.Where(x => !string.IsNullOrEmpty(x));