PropertyTypeConverter - Apply IFormattable when Format specified

snakefoot · snakefoot · commit 1b501760a8f5 · 2026-03-11T21:42:29.000+01:00
diff --git a/src/NLog/Config/PropertyTypeConverter.cs b/src/NLog/Config/PropertyTypeConverter.cs
@@ -115,17 +115,17 @@ internal static bool IsComplexType(Type type)
 
         private static bool TryConvertFromString(string propertyString, Type propertyType, string? format, IFormatProvider? formatProvider, out object? propertyValue)
         {
-            propertyValue = propertyString = propertyString.Trim();
+            propertyValue = propertyString;
 
             if (StringConverterLookup.TryGetValue(propertyType, out var converter))
             {
-                propertyValue = converter.Invoke(propertyString, format, formatProvider);
+                propertyValue = converter.Invoke(propertyString?.Trim() ?? string.Empty, format, formatProvider);
                 return true;
             }
 
             if (propertyType.IsEnum)
             {
-                return NLog.Common.ConversionHelpers.TryParseEnum(propertyString, propertyType, out propertyValue);
+                return NLog.Common.ConversionHelpers.TryParseEnum(propertyString?.Trim() ?? string.Empty, propertyType, out propertyValue);
             }
 
             if (PropertyHelper.TryTypeConverterConversion(propertyType, propertyString, out var convertedValue))
@@ -139,27 +139,35 @@ private static bool TryConvertFromString(string propertyString, Type propertyTyp
 
         private static object? ChangeObjectType(object propertyValue, Type propertyType, string? format, IFormatProvider? formatProvider)
         {
-            if (propertyValue is string propertyString && TryConvertFromString(propertyString, propertyType, format, formatProvider, out var fromStringValue))
+            if (propertyValue is string propertyString)
             {
-                return fromStringValue;
+                if (TryConvertFromString(propertyString, propertyType, format, formatProvider, out var fromStringValue))
+                    return fromStringValue;
             }
-
-            if (propertyValue is IConvertible convertibleValue)
+            else if (!string.IsNullOrEmpty(format) && propertyValue is IFormattable formattableValue)
             {
-                var typeCode = convertibleValue.GetTypeCode();
-                if (typeCode == TypeCode.DBNull)
-                    return convertibleValue;
-                if (typeCode == TypeCode.Empty)
-                    return null;
-            }
-            else if (TryConvertToType(propertyValue, propertyType, out var convertedValue))
-            {
-                return convertedValue;
-            }
+                var stringValue = formattableValue.ToString(format, formatProvider);
+                if (TryConvertFromString(stringValue, propertyType, format, formatProvider, out var fromStringValue))
+                    return fromStringValue;
 
-            if (!string.IsNullOrEmpty(format) && propertyValue is IFormattable formattableValue)
+                propertyValue = stringValue;
+            }
+            else
             {
-                propertyValue = formattableValue.ToString(format, formatProvider);
+                if (propertyValue is IConvertible convertibleValue)
+                {
+                    var typeCode = convertibleValue.GetTypeCode();
+                    if (typeCode == TypeCode.DBNull)
+                        return convertibleValue;
+                    if (typeCode == TypeCode.Empty)
+                        return null;
+                    if (typeCode == TypeCode.DateTime && propertyType == typeof(DateTimeOffset))
+                        return new DateTimeOffset(convertibleValue.ToDateTime(formatProvider));
+                }
+                else if (TryConvertToType(propertyValue, propertyType, out var convertedValue))
+                {
+                    return convertedValue;
+                }
             }
 
             return System.Convert.ChangeType(propertyValue, propertyType, formatProvider);
diff --git a/tests/NLog.UnitTests/Config/PropertyTypeConverterTests.cs b/tests/NLog.UnitTests/Config/PropertyTypeConverterTests.cs
@@ -223,6 +223,18 @@ public void Convert_FormattableToStringTest()
             Assert.Equal("0123", resultTyped);
         }
 
+        [Fact]
+        public void Convert_DateTimeToDateTimeOffset()
+        {
+            // Act
+            var dateTime = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
+            var result = _sut.Convert(dateTime, typeof(DateTimeOffset), "o", null);
+
+            // Assert
+            var resultTyped = Assert.IsType<DateTimeOffset>(result);
+            Assert.Equal(dateTime, resultTyped.DateTime);
+        }
+
         [Fact]
         public void Convert_NullableFormattableToStringTest()
         {
