Add `TimeZoneHelper`.

framework/src/Volo.Abp.Timing/Volo/Abp/Timing/TimeZoneHelper.cs

@@ -0,0 +1,27 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using TimeZoneConverter;
+
+namespace Volo.Abp.Timing;
+
+public static class TimeZoneHelper
+{
+    public static List<NameValue> GetTimezones(List<NameValue> timezones)
+    {
+        return timezones
+            .OrderBy(x => x.Name)
+            .Select(x => new NameValue( $"{x.Name} ({GetTimezoneOffset(TZConvert.GetTimeZoneInfo(x.Name))})", x.Name))
+            .ToList();
+    }
+
+    public static string GetTimezoneOffset(TimeZoneInfo timeZoneInfo)
+    {
+        if (timeZoneInfo.BaseUtcOffset < TimeSpan.Zero)
+        {
+            return "-" + timeZoneInfo.BaseUtcOffset.ToString(@"hh\:mm");
+        }
+
+        return "+" + timeZoneInfo.BaseUtcOffset.ToString(@"hh\:mm");
+    }
+}

modules/setting-management/src/Volo.Abp.SettingManagement.Application/Volo/Abp/SettingManagement/TimeZoneSettingsAppService.cs

@@ -1,9 +1,6 @@
-using System;
 using System.Collections.Generic;
-using System.Linq;
 using System.Threading.Tasks;
 using Microsoft.AspNetCore.Authorization;
-using TimeZoneConverter;
 using Volo.Abp.MultiTenancy;
 using Volo.Abp.Timing;
 
@@ -29,22 +26,7 @@ public class TimeZoneSettingsAppService : SettingManagementAppServiceBase, ITime
 
     public virtual Task<List<NameValue>> GetTimezonesAsync()
     {
-        var timezones = TimezoneProvider.GetWindowsTimezones()
-            .OrderBy(x => x.Name)
-            .Select(x => new NameValue( $"{x.Name} ({GetTimezoneOffset(TZConvert.GetTimeZoneInfo(x.Name))})", x.Name))
-            .ToList();
-
-        return Task.FromResult(timezones);
-    }
-
-    protected virtual string GetTimezoneOffset(TimeZoneInfo timeZoneInfo)
-    {
-        if (timeZoneInfo.BaseUtcOffset < TimeSpan.Zero)
-        {
-            return "-" + timeZoneInfo.BaseUtcOffset.ToString(@"hh\:mm");
-        }
-
-        return "+" + timeZoneInfo.BaseUtcOffset.ToString(@"hh\:mm");
+        return Task.FromResult(TimeZoneHelper.GetTimezones(TimezoneProvider.GetWindowsTimezones()));
     }
 
     public virtual async Task UpdateAsync(string timezone)