private static Expression WrapInTryCatch(Expression mappingBlock, IMemberMapperData mapperData)
{
var configuredCallback = mapperData.MapperContext.UserConfigurations.GetExceptionCallbackOrNull(mapperData);
var exceptionVariable = Parameters.Create <Exception>("ex");
Expression catchBody;
if (configuredCallback != null)
{
var callbackActionType = configuredCallback.Type.GetGenericArguments()[0];
Type[] contextTypes;
Expression contextAccess;
if (callbackActionType.IsGenericType())
{
contextTypes = callbackActionType.GetGenericArguments();
contextAccess = mapperData.GetAppropriateTypedMappingContextAccess(contextTypes);
}
else
{
contextTypes = new[] { mapperData.SourceType, mapperData.TargetType };
contextAccess = mapperData.MappingDataObject;
}
var exceptionContextCreateMethod = ObjectMappingExceptionData
.CreateMethod
.MakeGenericMethod(contextTypes);
var exceptionContextCreateCall = Expression.Call(
exceptionContextCreateMethod,
contextAccess,
exceptionVariable);
var callbackInvocation = Expression.Invoke(configuredCallback, exceptionContextCreateCall);
var returnDefault = Expression.Default(mappingBlock.Type);
catchBody = Expression.Block(callbackInvocation, returnDefault);
}
else
{
var exceptionFactoryMethod = MappingException.FactoryMethod
.MakeGenericMethod(mapperData.SourceType, mapperData.TargetType);
var mappingExceptionCreation = Expression.Call(
exceptionFactoryMethod,
mapperData.MappingDataObject,
exceptionVariable);
catchBody = Expression.Throw(mappingExceptionCreation, mappingBlock.Type);
}
var catchBlock = Expression.Catch(exceptionVariable, catchBody);
return(Expression.TryCatch(mappingBlock, catchBlock));
}
public Expression ToCatchBody(
Expression exceptionVariable,
Type returnType,
IMemberMapperData mapperData)
{
var callbackActionType = _callback.Type.GetGenericTypeArguments()[0];
Type[] contextTypes;
Expression contextAccess;
if (callbackActionType.IsGenericType())
{
contextTypes = callbackActionType.GetGenericTypeArguments();
contextAccess = mapperData.GetAppropriateTypedMappingContextAccess(contextTypes);
}
else
{
contextTypes = new[] { mapperData.SourceType, mapperData.TargetType };
contextAccess = mapperData.MappingDataObject;
}
var exceptionContextCreateMethod = ObjectMappingExceptionData
.CreateMethod
.MakeGenericMethod(contextTypes);
var createExceptionContextCall = Expression.Call(
exceptionContextCreateMethod,
contextAccess,
exceptionVariable);
var callbackInvocation = Expression.Invoke(_callback, createExceptionContextCall);
var returnDefault = returnType.ToDefaultExpression();
var configuredCatchBody = Expression.Block(callbackInvocation, returnDefault);
return(configuredCatchBody);
}