无法隐式转换类型“System.Collections.Generic.IEnumerable”到“System.Collections.Generic.List<字符串>”

Question

我有下面的代码：

List<string> aa = (from char c in source
                   select new { Data = c.ToString() }).ToList();

怎么办

List<string> aa = (from char c1 in source
                   from char c2 in source
                   select new { Data = string.Concat(c1, ".", c2)).ToList<string>();

但是编译时出现错误

无法将类型 'System.Collections.Generic.List' 隐式转换为 'System.Collections.Generic.List'

需要帮助。

Answer 1

IEnumerable<string> e = (from char c in source
                        select new { Data = c.ToString() }).Select(t = > t.Data);
// or
IEnumerable<string> e = from char c in source
                        select c.ToString();
// or
IEnumerable<string> e = source.Select(c = > c.ToString());

---

然后你可以调用ToList()：

List<string> l = (from char c in source
                  select new { Data = c.ToString() }).Select(t = > t.Data).ToList();
// or
List<string> l = (from char c in source
                  select c.ToString()).ToList();
// or
List<string> l = source.Select(c = > c.ToString()).ToList();

Answer 2

如果您希望它是 List，请删除匿名类型并添加 .ToList() 调用：

List<string> list = (from char c in source
                     select c.ToString()).ToList();

Answer 3

尝试

var lst= (from char c in source select c.ToString()).ToList();

Answer 4

如果您有像 "abcd" 这样的字符串源并且想要生成如下列表：

{ "a.a" },
{ "b.b" },
{ "c.c" },
{ "d.d" }

然后调用：

List<string> list = source.Select(c => String.Concat(c, ".", c)).ToList();

Answer 5

我认为答案如下

List<string> aa = (from char c in source
                    select c.ToString() ).ToList();

List<string> aa2 = (from char c1 in source
                    from char c2 in source
                    select string.Concat(c1, ".", c2)).ToList();