Fix the converting of `DateTime?` and `TimeSpan?`

#181

plugins/Booking/src/EasyAbp.EShop.Plugins.Booking.Application.Contracts/EasyAbp/EShop/Orders/CreateOrderLineDtoExtensions.cs

@@ -64,7 +64,7 @@ public static class CreateOrderLineDtoExtensions
 
     public static DateTime? FindBookingDate(this CreateOrderLineDto orderLine)
     {
-        return orderLine.GetProperty<DateTime?>(BookingOrderProperties.OrderLineBookingDate);
+        return orderLine.FindDateTimeProperty(BookingOrderProperties.OrderLineBookingDate);
     }
 
     public static DateTime GetBookingDate(this CreateOrderLineDto orderLine)
@@ -75,7 +75,7 @@ public static class CreateOrderLineDtoExtensions
 
     public static TimeSpan? FindBookingStartingTime(this CreateOrderLineDto orderLine)
     {
-        return orderLine.GetProperty<TimeSpan?>(BookingOrderProperties.OrderLineBookingStartingTime);
+        return orderLine.FindTimeSpanProperty(BookingOrderProperties.OrderLineBookingStartingTime);
     }
 
     public static TimeSpan GetBookingStartingTime(this CreateOrderLineDto orderLine)
@@ -86,7 +86,7 @@ public static class CreateOrderLineDtoExtensions
 
     public static TimeSpan? FindBookingDuration(this CreateOrderLineDto orderLine)
     {
-        return orderLine.GetProperty<TimeSpan?>(BookingOrderProperties.OrderLineBookingDuration);
+        return orderLine.FindTimeSpanProperty(BookingOrderProperties.OrderLineBookingDuration);
     }
 
     public static TimeSpan GetBookingDuration(this CreateOrderLineDto orderLine)

plugins/Booking/src/EasyAbp.EShop.Plugins.Booking.Application.Contracts/EasyAbp/EShop/Orders/HasExtraPropertiesExtensions.cs

@@ -0,0 +1,31 @@
+using System;
+using Volo.Abp.Data;
+
+namespace EasyAbp.EShop.Orders;
+
+public static class HasExtraPropertiesExtensions
+{
+    public static DateTime? FindDateTimeProperty(this IHasExtraProperties extraProperties, string name)
+    {
+        var objValue = extraProperties.GetProperty(name);
+
+        return objValue switch
+        {
+            null => null,
+            DateTime span => span,
+            _ => DateTime.Parse((string)objValue)
+        };
+    }
+
+    public static TimeSpan? FindTimeSpanProperty(this IHasExtraProperties extraProperties, string name)
+    {
+        var objValue = extraProperties.GetProperty(name);
+
+        return objValue switch
+        {
+            null => null,
+            TimeSpan span => span,
+            _ => TimeSpan.Parse((string)objValue)
+        };
+    }
+}

plugins/Booking/src/EasyAbp.EShop.Plugins.Booking.Application.Contracts/EasyAbp/EShop/Orders/OrderLineExtensions.cs

@@ -64,7 +64,7 @@ public static class OrderLineExtensions
 
     public static DateTime? FindBookingDate(this IOrderLine orderLine)
     {
-        return orderLine.GetProperty<DateTime?>(BookingOrderProperties.OrderLineBookingDate);
+        return orderLine.FindDateTimeProperty(BookingOrderProperties.OrderLineBookingDate);
     }
 
     public static DateTime GetBookingDate(this IOrderLine orderLine)
@@ -75,7 +75,7 @@ public static class OrderLineExtensions
 
     public static TimeSpan? FindBookingStartingTime(this IOrderLine orderLine)
     {
-        return orderLine.GetProperty<TimeSpan?>(BookingOrderProperties.OrderLineBookingStartingTime);
+        return orderLine.FindTimeSpanProperty(BookingOrderProperties.OrderLineBookingStartingTime);
     }
 
     public static TimeSpan GetBookingStartingTime(this IOrderLine orderLine)
@@ -86,7 +86,7 @@ public static class OrderLineExtensions
 
     public static TimeSpan? FindBookingDuration(this IOrderLine orderLine)
     {
-        return orderLine.GetProperty<TimeSpan?>(BookingOrderProperties.OrderLineBookingDuration);
+        return orderLine.FindTimeSpanProperty(BookingOrderProperties.OrderLineBookingDuration);
     }
 
     public static TimeSpan GetBookingDuration(this IOrderLine orderLine)