private IEntityChangeInformation ProcessExpression(Expression expression, IEntityChangeInformation entityChangeContainer, HashSet <string> processedProperties)
{
switch (expression.NodeType)
{
case ExpressionType.Assign:
return(ProcessBinaryExpression((BinaryExpression)expression, entityChangeContainer, processedProperties));
case ExpressionType.MemberAccess:
return(ProcessMemberExpression((MemberExpression)expression, entityChangeContainer, processedProperties));
case ExpressionType.Convert:
return(ProcessConvertExpression((UnaryExpression)expression, entityChangeContainer, processedProperties));
case ExpressionType.Constant:
return(ProcessConstantExpression((ConstantExpression)expression, entityChangeContainer));
case ExpressionType.Call:
return(ProcessCallExpression((MethodCallExpression)expression, entityChangeContainer, processedProperties));
case ExpressionType.Block:
return(ProcessBlockExpression((BlockExpression)expression, entityChangeContainer, processedProperties));
case ExpressionType.Lambda:
return(ProcessLambdaExpression((LambdaExpression)expression, entityChangeContainer, processedProperties));
}
return(entityChangeContainer);
}
public CompiledActionRule(Action <T> compiled, IEntityChangeInformation entityChangeInformation)
{
Compiled = compiled;
EntityChangeInformation = entityChangeInformation;
}
private IEntityChangeInformation ProcessBlockExpression(BlockExpression expression, IEntityChangeInformation entityChangeContainer, HashSet <string> processedProperties)
{
return(ProcessExpression(expression.Expressions.First(), entityChangeContainer, processedProperties));
}
private IEntityChangeInformation ProcessLambdaExpression(LambdaExpression expression, IEntityChangeInformation entityChangeContainer, HashSet <string> processedProperties)
{
return(ProcessExpression(expression.Body, entityChangeContainer, processedProperties));
}
private IEntityChangeInformation ProcessCallExpression(MethodCallExpression expression, IEntityChangeInformation entityChangeContainer, HashSet <string> processedProperties)
{
var expressionInfoAttribute = expression.Method.GetCustomAttribute <ExpressionInfoAttribute>();
var skipArguments = 0;
if (expressionInfoAttribute?.ExpressionPurposeType == ExpressionPurposeType.Filtering)
{
skipArguments = 2;
entityChangeContainer.Filter = new EntityChangeInformation
{
Member = entityChangeContainer.Member
};
var filterLambdaExpression = expression.Arguments.FirstOrDefault(arg => (arg as LambdaExpression)?.ReturnType == typeof(bool));
entityChangeContainer.Filter = ProcessExpression(filterLambdaExpression, entityChangeContainer.Filter, new HashSet <string>());
}
entityChangeContainer.Operation = expression.Method.Name + "(";
entityChangeContainer = expression.Arguments.Skip(skipArguments)
.Aggregate(entityChangeContainer, (accumulate, arg) => ProcessExpression(arg, accumulate, processedProperties));
if (!entityChangeContainer.Operation.EndsWith(")"))
{
entityChangeContainer.Operation += ")";
}
return(entityChangeContainer);
}
private IEntityChangeInformation ProcessBinaryExpression(BinaryExpression expression, IEntityChangeInformation entityChangeContainer, HashSet <string> processedProperties)
{
entityChangeContainer.Operation = expression.NodeType.ToString();
entityChangeContainer = ProcessExpression(expression.Left, entityChangeContainer, processedProperties);
return(ProcessExpression(expression.Right, entityChangeContainer, processedProperties));
}
private IEntityChangeInformation ProcessMemberExpression(MemberExpression expression, IEntityChangeInformation entityChangeContainer, HashSet <string> processedProperties)
{
var member = expression.Member;
var memberName = member.Name;
var expressionToString = expression.ToString();
if (processedProperties.Contains(expressionToString))
{
return(entityChangeContainer);
}
if (expression.Expression.NodeType == ExpressionType.MemberAccess)
{
entityChangeContainer = ProcessMemberExpression((MemberExpression)expression.Expression, entityChangeContainer, processedProperties);
}
if (!entityChangeContainer.Member.EndsWith("." + memberName))
{
entityChangeContainer.Member += "." + memberName;
}
processedProperties.Add(expressionToString);
return(entityChangeContainer);
}
private IEntityChangeInformation ProcessConstantExpression(ConstantExpression expression, IEntityChangeInformation entityChangeContainer)
{
entityChangeContainer.Values = entityChangeContainer.Values.Concat(new[] { expression.Value });
return(entityChangeContainer);
}
private IEntityChangeInformation ProcessConvertExpression(UnaryExpression expression, IEntityChangeInformation entityChangeContainer, HashSet <string> processedProperties)
{
return(ProcessExpression(expression.Operand, entityChangeContainer, processedProperties));
}
