Daylight time value calculate in Sharepoint and Asp.Net

Below is the code to get the Daylight time . Method public static DateTime GetZoneBasedDateTime(TimezoneName zone) { try { string strzoneId = GetEnumStringValue(zone); var dt = DateTime.UtcNow; var tz = TimeZoneInfo.FindSystemTimeZoneById(strzoneId); var utcOffset = new DateTimeOffset(dt, TimeSpan.Zero); DateTime dtResult = utcOffset.ToOffset(tz.GetUtcOffset(utcOffset)).DateTime; return dtResult; } catch (Exception ex) { WriteLogToFile("GetZoneTime(TimZoneName zone)", ex.Message, null, true); return DateTime.MinValue; } } } Enum public enum TimezoneName { [StringValueAttribute("Singapore Standard Time")] Asia = 1, [StringValueAttribute("W. Europe Standard Time")] Geneva = 2, [StringValueAttribute("Central Standard Time")] Hoston = 3, [StringValueAttribute("None")] None = 0 }

Enum with String Value Tagging

I have an requirement where I need to get a string value from Enum like KeyValue mapping. Below is the process to use Enum like a KeyValue mapping and get the keyvalue passing enum name . using System.Reflection; Declare a custom class. [AttributeUsage( AttributeTargets.Field )] public sealed class StringValueAttribute : Attribute { private string _value; public StringValueAttribute(string value) { _value = value; } public string Value { get { return _value; } } } Enum declaration. public enum TimezoneName { [StringValueAttribute("Singapore Standard Time")] Asia = 1, [StringValueAttribute("W. Europe Standard Time")] Geneva = 2, [StringValueAttribute("Central Standard Time")] Hoston = 3, [StringValueAttribute("None")] None = 0 } Get string value from Enum. public static string GetEnumStringValue(Enum evalue) { string output = null; if (evalue != null) { Type type = evalue.GetType(); FieldInfo fi = type.GetField(evalue.ToString()); StringValueAttribute[] attrs =fi.GetCustomAttributes(typeof(StringValueAttribute),false) as StringValueAttribute[]; if (attrs.Length > 0) { output = attrs[0].Value; } } return output; }

Write log for application

private void WriteLogToFile(string errorSource, string message, Exception exception, bool isNewLine) { try { // FileStream fs = new FileStream(ConfigurationManager.AppSettings.Get("ErrorLog"), FileMode.Append, FileAccess.Write, FileShare.ReadWrite); StreamWriter errorLog = new StreamWriter(fs); if (isNewLine) errorLog.WriteLine("-".PadRight(100, '-')); errorLog.WriteLine(DateTime.Now); if (errorSource != null) errorLog.WriteLine(errorSource); if (message != null) errorLog.WriteLine(message); if (exception != null) errorLog.WriteLine(exception); errorLog.Close(); fs.Close(); fs.Dispose(); } catch (Exception ex) { } }

DateTime Filter in CAML

While filtering data on datetime field use SPUtility.CreateISO8601DateTimeFromSystemDateTime(DateTime.UtcNow) for sharepoint in CAML.