How to get the all time zone using C#.Net?

public static DataTable GetTimeZoneTable(bool caseSensitive)
{
var systemTimeZones = TimeZoneInfo.GetSystemTimeZones();
string displayName = string.Empty;
DataTable dt = new DataTable("timezones");
dt.Columns.Add("ID", typeof(string));
dt.Columns.Add("DisplayName", typeof(string));
dt.Columns.Add("BaseUtcOffsetMinutes", typeof(int));
dt.Columns.Add("SupportsDaylightSavingTime", typeof(bool));
dt.PrimaryKey = new DataColumn[] { dt.Columns["ID"] };

foreach (TimeZoneInfo timeZone in systemTimeZones)
{
displayName = timeZone.DisplayName;
if (!caseSensitive) { displayName = displayName.ToLower(); }
dt.Rows.Add(timeZone.Id, displayName, Convert.ToInt32(timeZone.BaseUtcOffset.TotalMinutes), timeZone.SupportsDaylightSavingTime);
}
dt.AcceptChanges();
return dt;
}

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DatatTabe dt = GetTimeZoneTable(true);