C# List<string>转换成字符串 按指定的字符分隔

var stringExcept = result.Except(compareList).ToList(); //两个List获取差集
string notExistValue = String.Join(",", stringExcept.ToArray());//数组转换成string用逗号分隔

转自： https://www.cnblogs.com/huangtailang/p/4106314.html