Use "is not null" instead of "is object"

.editorconfig

@@ -137,7 +137,7 @@ csharp_style_implicit_object_creation_when_type_is_apparent = false:suggestion
 csharp_style_inlined_variable_declaration = true:suggestion
 csharp_style_prefer_index_operator = true:suggestion
 csharp_style_prefer_local_over_anonymous_function = true:suggestion
-csharp_style_prefer_null_check_over_type_check = true:suggestion
+csharp_style_prefer_null_check_over_type_check = true:warning
 csharp_style_prefer_range_operator = true:suggestion
 csharp_style_prefer_tuple_swap = true:suggestion
 csharp_style_prefer_utf8_string_literals = true:suggestion
@@ -149,6 +149,9 @@ dotnet_diagnostic.IDE0059.severity = none
 csharp_style_unused_value_expression_statement_preference = discard_variable:silent
 dotnet_diagnostic.IDE0058.severity = none
 
+# IDE0150: Prefer 'null' check over type check
+dotnet_diagnostic.IDE0150.severity = warning
+
 # 'using' directive preferences
 csharp_using_directive_placement = outside_namespace:warning
 

src/BMEcatSharp.Microsoft.Extensions.DependencyInjection/BMEcatSharpServiceCollectionExtensions.cs

@@ -9,7 +9,7 @@ public static IServiceCollection AddBMEcatSharp(this IServiceCollection services
         services.AddTransient(sp => sp.GetRequiredService<IOptions<BMEcatOptions>>().Value);
         services.AddTransient(sp => sp.GetRequiredService<IOptions<BMEcatOptions>>().Value.Serialization);
 
-        if (configureOptions is object)
+        if (configureOptions is not null)
         {
             services.Configure(configureOptions);
         }

src/BMEcatSharp/Types/Catalog.cs

@@ -145,7 +145,7 @@ public string? VersionForSerializer
     public BMEcatDatetime? Date { get; set; }
     [EditorBrowsable(EditorBrowsableState.Never)]
 #pragma warning disable CS0618 // Type or member is obsolete
-    public bool DateSpecified => Date is object;
+    public bool DateSpecified => Date is not null;
 #pragma warning restore CS0618 // Type or member is obsolete
 
     /// <summary>

src/BMEcatSharp/Types/FeatureContent.cs

@@ -91,7 +91,7 @@ public FeatureContent(FeatureDataTypeValues dataType)
     [BMEXmlElement("FT_UNIT")]
     public string? Unit { get; set; }
     [EditorBrowsable(EditorBrowsableState.Never)]
-    public bool UnitSpecified => Unit is string;
+    public bool UnitSpecified => Unit is not null;
     [XmlIgnore]
     public Unit? UnitAsStandardUnit
     {

src/BMEcatSharp/Xml/BMEcatXmlSerializerFactory.cs

@@ -13,13 +13,13 @@ public BMEcatXmlSerializerFactory(BMEcatXmlSerializerOptions options)
 
         udxMappings = new Dictionary<string, Type>();
 
-        if (options?.IncludeUdxTypes is object)
+        if (options?.IncludeUdxTypes is not null)
         {
             foreach (var type in options.IncludeUdxTypes)
             {
                 var tagName = $"UDX.{type.Name.ToUpperInvariant()}";
                 var root = type.GetCustomAttribute<XmlRootAttribute>();
-                if (root is object)
+                if (root is not null)
                 {
                     tagName = root.ElementName;
                 }

src/OpenTransSharp.Microsoft.Extensions.DependencyInjection/OpenTransSharpServiceCollectionExtensions.cs

@@ -9,7 +9,7 @@ public static IServiceCollection AddOpenTransSharp(this IServiceCollection servi
         services.AddTransient(sp => sp.GetRequiredService<IOptions<OpenTransOptions>>().Value);
         services.AddTransient(sp => sp.GetRequiredService<IOptions<OpenTransOptions>>().Value.Serialization);
 
-        if (configureOptions is object)
+        if (configureOptions is not null)
         {
             services.Configure(configureOptions);
         }