c# - LINQ:如何在选择期间转换查询结果？

Question

这将返回一个 strings 列表:

var filesizes = from fd in files
                from tag in fd.Tags
                where tag.Id == ID.FILESIZE
                select tag.Value;

下面的方法行不通，但是否有一种方法可以在查询期间执行类似将 string 转换为 int 的操作？

var filesizes = from fd in files
                from tag in fd.Tags
                where tag.Id == ID.FILESIZE
                select new { int.Parse(tag.Value) };

或者我应该只使用 ConvertAll as suggested here ？

Answer 1

你可以这样做:

var filesizes = from fd in files
                from tag in fd.Tags
                where tag.Id == ID.FILESIZE
                select new { FileSize = int.Parse(tag.Value) };

或

var filesizes = from fd in files
                from tag in fd.Tags
                where tag.Id == ID.FILESIZE
                select int.Parse(tag.Value);