Question

I am new to lambda expressions; I am learning by implementing them. I have a question on how to convert a for-loop into a lambda expression.

EnumHelper.GetEnumFromString is a helper method that takes the string description and sends back the enum.

 [Flags]
    public enum Colors
    {
        [DescriptionAttribute("YL")]
        Yellow = 1,
        [DescriptionAttribute("RD")]
        Red = 2,
        [DescriptionAttribute("GR")]
        Green = 4
    }

 string colorStr = "GR,RD";
 List<Colors> clrs = colorStr.Split(new char[] { ',' }).Select(p => EnumHelper.GetEnumFromString<Colors>(p)).ToList();
 Colors currentValidColors = Colors.Green;

    for (int i = 0; i < clrs .Count; i++)
    {
         if (i == 0)
              currentValidColors = clrs [i];
          else
              currentValidColors = currentValidColors | clrs [i];
    }

Answer 1

Is this what you are thinking of? ForEach extension method is only available for generic lists.

Colors currentValidColors = 0;
colorStr.Split(new char[] { ',' })
.Select(p => EnumHelper.GetEnumFromString<Colors>(p))
.ToList()
.ForEach(c => currentValidColors |= c);