c#ListのtoString拡張

Extension.cs

namespace kamiya.util{
	public static class Extensions {
		public static string ToString<T>(this List<T> list,Func<T,string> toStr = null,string format = "{0},"){
			//default
			if (toStr == null) toStr = (t) => t.ToString();
			
			var strs = (from p in list select (toStr(p))).ToArray();
			var sb = new StringBuilder("[");
			foreach (var str in strs) {
				sb.AppendFormat(format, str);
			}
			sb.AppendLine("]");
			return sb.ToString();
		}
	}
}