Merge pull request #585 from riccardofrancesconi/EmitFractionDigitsDataAnnotationInGeneratedModels

Add support for custom FractionDigitsAttribute

Author: mganss

README.md

@@ -210,6 +210,11 @@ Options:
                              force URI scheme when resolving URLs (default is
                                none; can be: none, same, or any defined value
                                for scheme, like https or http)
+      --ema, --emitMetadataAttributes
+                             emit metadata helper attributes (default is false)
+      --mn, --metadataNamespace=VALUE
+                             namespace for generated metadata helper attributes (
+                               default is XmlSchemaClassGenerator.Metadata)
 </pre>
 
 For use from code use the [library NuGet package](https://www.nuget.org/packages/XmlSchemaClassGenerator-beta/):
@@ -236,12 +241,41 @@ Specifying the `NamespaceProvider` is optional. If you don't provide one, C# nam
 var generator = new Generator
 {
     NamespaceProvider = new NamespaceProvider
-    { 
+    {
         GenerateNamespace = key => ...
     }
 };
 ```
 
+### Metadata attributes
+
+When `EmitMetadataAttributes` is enabled, the generator emits custom attributes for XML schema restrictions that aren't covered by standard DataAnnotations. For example, `xs:fractionDigits` becomes `FractionDigitsAttribute`:
+
+**Schema:**
+```xml
+<xs:element name="price">
+  <xs:simpleType>
+    <xs:restriction base="xs:decimal">
+      <xs:fractionDigits value="2"/>
+    </xs:restriction>
+  </xs:simpleType>
+</xs:element>
+```
+
+**Command line:**
+```
+xscgen --ema --mn MyApp.Metadata -o Generated schema.xsd
+```
+
+**Generated code:**
+```C#
+[System.ComponentModel.DataAnnotations.Required()]
+[MyApp.Metadata.FractionDigits(2)]
+public decimal Price { get; set; }
+```
+
+The attribute definition is automatically generated in the specified namespace. If not specified, the default namespace is `XmlSchemaClassGenerator.Metadata`.
+
 ### Mapping xsd files to C# namespaces
 
 Using the optional `|` syntax of the `-n` command line option you can map individual xsd files to C# namespaces. If you have several input files using the same XML namespace you can still generate an individual C# namespace for the types defined within a single xsd file. For example, if you have two input files `a.xsd` and `b.xsd` both of which have the same `targetNamespace` of `http://example.com/namespace` you can generate the C# namespaces `Example.NamespaceA` and `Example.NamespaceB`:

XmlSchemaClassGenerator.Console/Program.cs

@@ -69,10 +69,12 @@ static int Main(string[] args)
         var separateNamespaceHierarchy = false;
         var serializeEmptyCollections = false;
         var allowDtdParse = false;
-        var omitXmlIncludeAttribute = false;
-        var enumCollection = false;
-        NamingScheme? namingScheme = null;
+        var omitXmlIncludeAttribute = false;
+        var enumCollection = false;
+        NamingScheme? namingScheme = null;
         var forceUriScheme = "none";
+        var emitMetadataAttributes = false;
+        var metadataNamespace = GeneratorConfiguration.DefaultMetadataNamespace;
 
 
         var options = new OptionSet {
@@ -171,7 +173,7 @@ A file name may be given by appending a pipe sign (|) followed by a file name (l
             { "uc|unionCommonType", "generate a common type for unions if possible (default is false)", v => unionCommonType = v != null },
             { "ec|serializeEmptyCollections", "serialize empty collections (default is false)", v => serializeEmptyCollections = v != null },
             { "dtd|allowDtdParse", "allows dtd parse (default is false)", v => allowDtdParse = v != null },
-            { "oxi|omitXmlIncludeAttribute", "omit generation of XmlIncludeAttribute for derived types (default is false)", v => omitXmlIncludeAttribute = v != null },
+            { "oxi|omitXmlIncludeAttribute", "omit generation of XmlIncludeAttribute for derived types (default is false)", v => omitXmlIncludeAttribute = v != null },
             { "ecl|enumCollection", "generate typed enum collections for xs:list types instead of string collections (default is false)", v => enumCollection = v != null },
             { "ns|namingScheme=", @"use the specified naming scheme for class and property names (default is Pascal; can be: Direct, Pascal, Legacy)",
                 v =>
@@ -185,7 +187,9 @@ A file name may be given by appending a pipe sign (|) followed by a file name (l
                     };
                 }
             },
-            { "fu|forceUriScheme=", "force URI scheme when resolving URLs (default is none; can be: none, same, or any defined value for scheme, like https or http)", v => forceUriScheme = v }
+            { "fu|forceUriScheme=", "force URI scheme when resolving URLs (default is none; can be: none, same, or any defined value for scheme, like https or http)", v => forceUriScheme = v },
+            { "ema|emitMetadataAttributes", "emit metadata helper attributes (default is false)", v => emitMetadataAttributes = v != null },
+            { "mn|metadataNamespace=", $"namespace for generated metadata helper attributes (default is {GeneratorConfiguration.DefaultMetadataNamespace})", v => metadataNamespace = v }
         };
 
         var globsAndUris = options.Parse(args);
@@ -274,9 +278,11 @@ A file name may be given by appending a pipe sign (|) followed by a file name (l
             SeparateNamespaceHierarchy = separateNamespaceHierarchy,
             SerializeEmptyCollections = serializeEmptyCollections,
             AllowDtdParse = allowDtdParse,
-            OmitXmlIncludeAttribute = omitXmlIncludeAttribute,
-            EnumCollection = enumCollection,
-            ForceUriScheme = forceUriScheme
+            OmitXmlIncludeAttribute = omitXmlIncludeAttribute,
+            EnumCollection = enumCollection,
+            ForceUriScheme = forceUriScheme,
+            EmitMetadataAttributes = emitMetadataAttributes,
+            MetadataNamespace = metadataNamespace
         };
 
         if (namingScheme != null)