/// <summary>
/// Adds a <see cref="IExpressionHandler" /> to be used when handling expressions.
/// </summary>
/// <param name="expressionType">
/// The <see cref="ExpressionType" /> handled by the given <see cref="IExpressionHandler" />
/// </param>
/// <param name="handler">
/// The <see cref="IExpressionHandler" />.
/// </param>
/// <param name="isDefaultHandler">
/// A value indicating whether the handler is added internally (true) or externally using
/// <see cref="FlowQueryHelper.AddExpressionHandler" /> (false).
/// </param>
/// <exception cref="ArgumentNullException">
/// <paramref name="handler" /> is null.
/// </exception>
private static void AddHandler
(
ExpressionType expressionType,
IExpressionHandler handler,
bool isDefaultHandler = true
)
{
lock (ExpressionHandlerLock)
{
if (handler == null)
{
throw new ArgumentNullException("handler");
}
Dictionary <ExpressionType, HashSet <IExpressionHandler> > collection = isDefaultHandler
? DefaultExpressionHandlers
: CustomExpressionHandlers;
HashSet <IExpressionHandler> handlers;
bool found = collection.TryGetValue(expressionType, out handlers);
if (found)
{
handlers.Add(handler);
}
else
{
collection.Add(expressionType, new HashSet <IExpressionHandler> {
handler
});
}
}
}
/// <summary>
/// Adds a <see cref="IMethodCallExpressionHandler" /> to be used when handling method calls.
/// </summary>
/// <param name="expressionType">
/// The <see cref="ExpressionType" /> handled by the given <see cref="IExpressionHandler" />
/// </param>
/// <param name="handler">
/// The <see cref="IExpressionHandler" />.
/// </param>
/// <exception cref="ArgumentNullException">
/// <paramref name="handler" /> is null.
/// </exception>
public static void AddExpressionHandler
(
ExpressionType expressionType,
IExpressionHandler handler
)
{
AddHandler(expressionType, handler, false);
}
/// <summary>
/// Adds a <see cref="IExpressionHandler" /> to be used when handling method call expressions.
/// </summary>
/// <param name="handler">
/// The <see cref="IExpressionHandler" />.
/// </param>
/// <param name="isDefaultHandler">
/// A value indicating whether the handler is added internally (true) or externally using
/// <see cref="FlowQueryHelper.AddExpressionHandler" /> (false).
/// </param>
/// <exception cref="ArgumentNullException">
/// <paramref name="handler" /> is null.
/// </exception>
private static void AddCallHandler
(
IExpressionHandler handler,
bool isDefaultHandler = true
)
{
AddHandler(ExpressionType.Call, handler, isDefaultHandler);
}
/// <summary>
/// Evaluates an expression and applies the results to an existing object
/// </summary>
/// <param name="Expression">the expression to evaluate</param>
/// <param name="existingObject">the object to apply to</param>
/// <returns>the evaluated object</returns>
public object Evaluate(Expression expression, object existingObject)
{
Expression oldExpr = Current;
_currentExpression = expression;
IExpressionHandler handler = Settings.ExpressionHandlers.GetHandler(expression);
object result = handler.Evaluate(expression, existingObject, this);
_currentExpression = oldExpr ?? _currentExpression;
return(result);
}
/// <summary>
/// Sets the current model.
/// </summary>
/// <param name="model"></param>
public void SetModel(Model.Model model)
{
this.model = model;
ExpressionHandler = new ExpressionHandler(model);
}
public override IResult Parse(object source)
{
if (null == source)
{
throw new ArgumentNullException("source");
}
ContainerWebPart webPart = source as ContainerWebPart;
if (null == webPart)
{
throw new ArgumentException("source is not an ContainerWebPart");
}
IConfiguration config = webPart.Configuration;
if (null == config)
{
throw new ArgumentException("missing configuration");
}
IValidationManager validationManager = webPart.ValidationManager;
if (null == validationManager)
{
throw new ArgumentException("missing validation manager");
}
base.Parse(source);
if (config.Sections.ContainsKey("Template"))
{
IConfigurationSection templateConfig = config.GetConfigurationSectionReference("Template");
webPart.TemplateConfig = templateConfig;
}
else
{
webPart.TemplateConfig = config.NewConfigurationSectionInstance("Template");
}
if (config.Sections.ContainsKey("Validation"))
{
foreach (IConfigurationElement element in config.Sections["Validation"].Elements.Values)
{
IValidationTask task = validationManager.NewValidationTaskInstance();
if (element.Attributes.ContainsKey("target"))
{
task.Target = element.GetAttributeReference("target").Value;
}
if (element.Attributes.ContainsKey("member"))
{
task.Member = element.GetAttributeReference("member").Value.ToString();
}
foreach (IConfigurationElement handlerElement in element.Elements.Values)
{
if (handlerElement.Attributes.ContainsKey("handlerKey"))
{
string handlerKey = handlerElement.GetAttributeReference("handlerKey").Value.ToString();
IValidationHandler handler = validationManager.Handler(handlerKey);
if ("expression" == handlerKey)
{
IExpressionHandler expressionHandler = handler as IExpressionHandler;
IEnumerator <IConfigurationElement> enumerator = handlerElement.Elements.Values.GetEnumerator();
if (enumerator.MoveNext())
{
IConfigurationElement expressionElement = enumerator.Current;
expressionHandler.Expression = (validationManager.ExpressionsManager.Token(expressionElement.GetAttributeReference("type").Value.ToString()) as IExpression);
if (null == expressionHandler.Expression)
{
throw new InvalidOperationException("Token is not an IExpression");
}
expressionHandler.Expression.Make(expressionElement, validationManager.ExpressionsManager);
}
}
task.Handlers.Add(handler);
}
}
validationManager.RegisterTask(task);
}
}
if (config.Sections.ContainsKey("Checks"))
{
foreach (IConfigurationElement element in config.Sections["Checks"].Elements.Values)
{
if (element.Attributes.ContainsKey("command"))
{
string command = element.GetAttributeReference("command").Value.ToString();
webPart.Checks.Add(command, new List <Container.CheckDefinition>());
foreach (IConfigurationElement checkElement in element.Elements.Values)
{
Container.CheckDefinition check = new Container.CheckDefinition();
if (checkElement.Attributes.ContainsKey("error"))
{
check.Error = checkElement.GetAttributeReference("error").Value.ToString();
}
if (checkElement.Attributes.ContainsKey("milestone"))
{
check.Milestone = checkElement.GetAttributeReference("milestone").Value.ToString();
}
IEnumerator <IConfigurationElement> enumerator = checkElement.Elements.Values.GetEnumerator();
if (enumerator.MoveNext())
{
IConfigurationElement expressionElement = enumerator.Current;
IExpression expression = webPart.ExpressionsManager.Token(expressionElement.GetAttributeReference("type").Value.ToString()) as IExpression;
if (null == expression)
{
throw new InvalidOperationException("Token is not an IExpression");
}
expression.Make(expressionElement, webPart.ExpressionsManager);
check.Expression = expression;
}
webPart.Checks[command].Add(check);
}
}
}
}
return(null);
}
public object Evaluate(Expression Expression, object existingObject)
{
IExpressionHandler handler = _context.ExpressionHandlers.GetHandler(Expression);
return(handler.Evaluate(Expression, existingObject, this));
}
