// NOTE : these are here as Reflection member search is pretty expensive, and we want that to be done once.
// Also, making these static would cause this class to fail loading if we rename members of ExportDefinition.
//private static readonly PropertyInfo _exportDefinitionContractNameProperty = typeof(ExportDefinition).GetProperty("ContractName");
//private static readonly PropertyInfo _exportDefinitionMetadataProperty = typeof(ExportDefinition).GetProperty("Metadata");
//private static readonly MethodInfo _metadataContainsKeyMethod = typeof(IDictionary<string, object>).GetMethod("ContainsKey");
//private static readonly MethodInfo _metadataItemMethod = typeof(IDictionary<string, object>).GetMethod("get_Item");
//private static readonly MethodInfo _metadataEqualsMethod = typeof(object).GetMethod("Equals", new Type[] { typeof(object) });
//private static readonly MethodInfo _typeIsInstanceOfTypeMethod = typeof(Type).GetMethod("IsInstanceOfType");
public static Func <ExportDefinition, bool> CreateConstraint(IEnumerable <KeyValuePair <string, Type> > requiredMetadata)
{
if (requiredMetadata == null)
{
return(null);
}
var constraintInstance = new ConstraintInstance(requiredMetadata);
var constraint = constraintInstance.GetExportDefinitionConstraint();
return(constraint);
//ParameterExpression parameter = Expression.Parameter(typeof(ExportDefinition), "exportDefinition");
//Expression metadataConstraintBody = null;
//if (requiredMetadata != null)
//{
// metadataConstraintBody = ConstraintServices.CreateMetadataConstraintBody(requiredMetadata, parameter);
//}
//if (metadataConstraintBody != null)
//{
// return Expression.Lambda<Func<ExportDefinition, bool>>(metadataConstraintBody, parameter);
//}
//return null;
}
public static Func <ExportDefinition, bool> CreateConstraint(
string contractName,
string requiredTypeIdentity,
IEnumerable <KeyValuePair <string, Type> > requiredMetadata,
CreationPolicy requiredCreationPolicy)
{
var constraintInstance = new ConstraintInstance(contractName, requiredTypeIdentity, requiredMetadata, requiredCreationPolicy);
var constraint = constraintInstance.GetExportDefinitionConstraint();
return(constraint);
//ParameterExpression parameter = Expression.Parameter(typeof(ExportDefinition), "exportDefinition");
//Expression constraintBody = ConstraintServices.CreateContractConstraintBody(contractName, parameter);
//if (!string.IsNullOrEmpty(requiredTypeIdentity))
//{
// Expression typeIdentityConstraintBody = ConstraintServices.CreateTypeIdentityContraint(requiredTypeIdentity, parameter);
// constraintBody = Expression.AndAlso(constraintBody, typeIdentityConstraintBody);
//}
//if (requiredMetadata != null)
//{
// Expression metadataConstraintBody = ConstraintServices.CreateMetadataConstraintBody(requiredMetadata, parameter);
// if (metadataConstraintBody != null)
// {
// constraintBody = Expression.AndAlso(constraintBody, metadataConstraintBody);
// }
//}
//if (requiredCreationPolicy != CreationPolicy.Any)
//{
// Expression policyConstraintBody = ConstraintServices.CreateCreationPolicyContraint(requiredCreationPolicy, parameter);
// constraintBody = Expression.AndAlso(constraintBody, policyConstraintBody);
//}
//Expression<Func<ExportDefinition, bool>> constraint = Expression.Lambda<Func<ExportDefinition, bool>>(constraintBody, parameter);
//return constraint;
}
