是否有任何简单的LINQ表达式将我的整个List<string>集合项连接到具有分隔符字符的单个字符串?

如果集合是自定义对象而不是字符串呢?假设我需要连接object。name。


当前回答

我认为如果你在扩展方法中定义逻辑,代码将更易于阅读:

public static class EnumerableExtensions { 
  public static string Join<T>(this IEnumerable<T> self, string separator) {  
    return String.Join(separator, self.Select(e => e.ToString()).ToArray()); 
  } 
} 

public class Person {  
  public string FirstName { get; set; }  
  public string LastName { get; set; }  
  public override string ToString() {
    return string.Format("{0} {1}", FirstName, LastName);
  }
}  

// ...

List<Person> people = new List<Person>();
// ...
string fullNames = people.Join(", ");
string lastNames = people.Select(p => p.LastName).Join(", ");

其他回答

List<string> strings = new List<string>() { "ABC", "DEF", "GHI" };
string s = strings.Aggregate((a, b) => a + ',' + b);

好问题。我一直在用

List<string> myStrings = new List<string>{ "ours", "mine", "yours"};
string joinedString = string.Join(", ", myStrings.ToArray());

它不是LINQ,但它可以工作。

using System.Linq;

public class Person
{
  string FirstName { get; set; }
  string LastName { get; set; }
}

List<Person> persons = new List<Person>();

string listOfPersons = string.Join(",", persons.Select(p => p.FirstName));

你可以简单地使用:

List<string> items = new List<string>() { "foo", "boo", "john", "doe" };

Console.WriteLine(string.Join(",", items));

编码快乐!

我认为如果你在扩展方法中定义逻辑,代码将更易于阅读:

public static class EnumerableExtensions { 
  public static string Join<T>(this IEnumerable<T> self, string separator) {  
    return String.Join(separator, self.Select(e => e.ToString()).ToArray()); 
  } 
} 

public class Person {  
  public string FirstName { get; set; }  
  public string LastName { get; set; }  
  public override string ToString() {
    return string.Format("{0} {1}", FirstName, LastName);
  }
}  

// ...

List<Person> people = new List<Person>();
// ...
string fullNames = people.Join(", ");
string lastNames = people.Select(p => p.LastName).Join(", ");