用lambda连接对象的字符串属性

Question

请考虑以下事项:

public class MyObject
{
   public bool B;
   public string Txt;
}
List<MyObject> list; //list of a bunch of MyObject's 

使用lambda表达式，我如何生成一个由逗号分隔的Txt值组成的字符串，其中B为真?

Answer 1

for .net 3.5:

string.Join(",", list.Where(o => o.B).Select(o => o.Txt).ToArray())

:

string.Join(",", list.Where(o => o.B).Select(o => o.Txt))

Answer 2

string myString = string.Join(",", list.Where(x => x.B).Select(x=>x.Txt));

Answer 3

var strFinal = "";
myList.ForEach(pq => strFinal += ", " + pq.ItemId);