/// <summary>
/// Generates the metadata class for the given object (entity or complex object)
/// </summary>
/// <param name="codeGenContext">The context to use to generate code.</param>
/// <param name="optionalSuffix">If not null, optional suffix to class name and namespace</param>
/// <param name="type">The type of the object for which to generate the metadata class.</param>
/// <returns><c>true</c> means at least some code was generated.</returns>
public bool GenerateMetadataClass(CodeGenContext codeGenContext, string optionalSuffix, Type type)
{
// If already have a buddy class, bypass all this logic
// Use soft dependency (string name) to avoid static dependency on DataAnnotations.
// We do this because this wizard must run from the GAC, and DataAnnotations will not necessarily be in the GAC too.
Type buddyClassType = TypeUtilities.GetAssociatedMetadataType(type);
if (buddyClassType != null)
{
return(false);
}
string className = type.Name;
string classNamespace = type.Namespace;
bool addSuffix = !string.IsNullOrEmpty(optionalSuffix);
if (addSuffix)
{
className += optionalSuffix;
classNamespace += optionalSuffix;
}
// Every object could have a unique namespace (odd, but true)
// So we logically create a new namespace for each object. Those
// sharing a namespace will reuse the CodeNamespace.
// We allow the caller to specify in case it needs to override that
// namespace. Unit testing is such a scenario
CodeNamespace codeNamespace = codeGenContext.GetOrGenNamespace(classNamespace);
// If we redirected to a different namespace than the object, import the real object's namespace
if (addSuffix)
{
CodeGenUtilities.AddImportIfNeeded(codeNamespace, type.Namespace);
}
// Name of buddy class is $objectClassName$Metadata (e.g. Orders --> OrdersMetadata)
string buddyClassName = className + "Metadata";
// We use the full outer.inner type naming convention for VB because they cannot resolve it otherwise.
// C# can currently resolve it due to a bug in the compiler, but it is safer to use the legal syntax here.
string fullBuddyClassName = className + "." + buddyClassName;
CodeTypeDeclaration objectClass = null;
// public class $objectType$ { }
objectClass = CodeGenUtilities.CreateTypeDeclaration(className, classNamespace);
objectClass.IsPartial = true;
objectClass.TypeAttributes = TypeAttributes.Public;
// Add explanatory comments about what the [MetadataTypeAttribute] does
objectClass.Comments.Add(new CodeCommentStatement(String.Format(CultureInfo.CurrentCulture, Resources.BusinessLogicClass_Entity_Partial_Class_Remarks, buddyClassName, className), false));
// [MetadataType(typeof($objectType$.$objectType$_Metadata))]
CodeAttributeDeclaration attr = CodeGenUtilities.CreateAttributeDeclaration(BusinessLogicClassConstants.MetadataTypeAttributeTypeName);
CodeAttributeArgument attrArg = new CodeAttributeArgument(new CodeTypeOfExpression(fullBuddyClassName));
attr.Arguments.Add(attrArg);
objectClass.CustomAttributes.Add(attr);
// public sealed class $objectType$_Metadata { }
// (note: cannot set 'static' modified from CodeDom.)
CodeTypeDeclaration buddyClass = CodeGenUtilities.CreateTypeDeclaration(buddyClassName, classNamespace);
// Both VB and C# use a friend/public buddy class. A private buddy class does not
// compile in VB, and it compiles in C# only due to a bug.
buddyClass.TypeAttributes = TypeAttributes.Sealed | TypeAttributes.NestedAssembly;
bool generatedProperty = false;
// Generate a developer comment describing what this class does
buddyClass.Comments.Add(new CodeCommentStatement(String.Format(CultureInfo.CurrentCulture, Resources.Buddy_Class_Remarks, type.Name)));
// Add a language-specific example
string explanation = codeGenContext.IsCSharp ? Resources.Buddy_Class_Remarks_CSharp : Resources.Buddy_Class_Remarks_VB;
buddyClass.Comments.Add(new CodeCommentStatement(explanation, false));
// Generate a private ctor to make it impossible to instantiate this class
CodeConstructor ctor = new CodeConstructor();
ctor.Attributes = MemberAttributes.Private;
ctor.Comments.Add(new CodeCommentStatement(Resources.BusinessLogicClass_Private_Ctor_Comment));
buddyClass.Members.Add(ctor);
// Sort by name order for baseline predictability
foreach (PropertyInfo propertyInfo in type.GetProperties(BindingFlags.Instance | BindingFlags.Public | BindingFlags.DeclaredOnly).OrderBy(p => p.Name))
{
// CodeDom does not support auto-implemented properties, so we will generate fields and then transform them into properties
Type propType = propertyInfo.PropertyType;
if (propType.IsVisible && propertyInfo.GetGetMethod() != null && this.CanGeneratePropertyOfType(propType))
{
// Add an import for this property type's namespace if needed
CodeGenUtilities.AddImportIfNeeded(codeNamespace, propertyInfo.PropertyType.Namespace);
CodeSnippetTypeMember property = CodeGenUtilities.CreateAutomaticPropertyDeclaration(codeGenContext, buddyClass, propertyInfo, !string.IsNullOrEmpty(codeNamespace.Name) /* insideNamespace */);
buddyClass.Members.Add(property);
generatedProperty = true;
}
}
// Don't generate anything if the buddy class is empty
if (generatedProperty)
{
// Add the partial object class to the namespace
codeNamespace.Types.Add(objectClass);
// Add the metadata class as a nested class inside the partial object class
objectClass.Members.Add(buddyClass);
}
// false if no properties were generated, indicating no code should be emitted
return(generatedProperty);
}
