public DataContextStack(Type type, DataContextStack parent = null)
{
Parent = parent;
DataContextType = type;
RootControlType = parent?.RootControlType;
//if (parent == null) Parameters = new List<Type>();
//else Parameters = parent.Parameters;
}
public override Type GetChildDataContextType(Type dataContext, DataContextStack controlContextStack, ResolvedControl control, DotvvmProperty dproperty = null)
{
var property = DotvvmProperty.ResolveProperty(control.Metadata.Type, PropertyName);
ResolvedPropertySetter propertyValue;
if (control.Properties.TryGetValue(property, out propertyValue))
{
var binding = propertyValue as ResolvedPropertyBinding;
if (binding == null) return dataContext;
return binding.Binding.GetExpression().Type;
}
else return dataContext;
}
public object ExecuteBinding(string expression, object[] contexts, DotvvmControl control)
{
var context = new DataContextStack(contexts.FirstOrDefault()?.GetType() ?? typeof(object));
context.RootControlType = control?.GetType() ?? typeof(DotvvmControl);
for (int i = 1; i < contexts.Length; i++)
{
context = new DataContextStack(contexts[i].GetType(), context);
}
var parser = new BindingParser();
var expressionTree = parser.Parse(expression, context);
return BindingCompiler.CompileToDelegate(expressionTree, context)(contexts, control);
}
// public static Expression GetDataContextExpression(DataContextStack dataContextStack, ResolvedControl control, DotvvmProperty property = null)
//{
// var attributes = control.Metadata.Type.GetCustomAttributes<DataContextChangeAttribute>();
// Expression dataContextExpression = Expression.Parameter(dataContextStack.DataContextType, Constants.ThisSpecialBindingProperty);
// var paramDataContextExpression = dataContextExpression;
// foreach (var attribute in attributes)
// {
// // TODO: assign to varialbes to reduce multiple calls ?
// dataContextExpression = attribute.GetChildDataContextType(dataContextExpression, dataContextStack, control, property);
// }
// return dataContextExpression == paramDataContextExpression ? null : dataContextExpression;
//}
public static Type GetDataContextExpression(DataContextStack dataContextStack, ResolvedControl control, DotvvmProperty property = null)
{
var attributes = property == null ? control.Metadata.Type.GetCustomAttributes<DataContextChangeAttribute>() : property.PropertyInfo?.GetCustomAttributes<DataContextChangeAttribute>();
if (attributes == null) return null;
var type = dataContextStack.DataContextType;
var paramDataContextExpression = type;
foreach (var attribute in attributes)
{
// TODO: assign to varialbes to reduce multiple calls ?
type = attribute.GetChildDataContextType(type, dataContextStack, control, property);
}
return type == paramDataContextExpression ? null : type;
}
/// <summary>
/// Emits value or binding and returns
/// </summary>
protected ExpressionSyntax ProcessBindingOrValue(object obj, DataContextStack dataContext)
{
var binding = obj as ResolvedBinding;
if (binding != null) return ProcessBinding(binding);
else return emitter.EmitValue(obj);
}
protected void ProcessHtmlAttributes(string controlName, IDictionary<string, object> attributes, DataContextStack dataContext)
{
foreach (var attr in attributes)
{
var value = ProcessBindingOrValue(attr.Value, dataContext);
emitter.EmitAddHtmlAttribute(controlName, attr.Key, value);
}
}
//public override Expression GetChildDataContextType(Expression dataContext, DataContextStack controlContextStack, ResolvedControl control, DotvvmProperty property = null)
//{
// return ExpressionUtils.Indexer(dataContext, controlContextStack.GetNextParameter(typeof(int)));
//}
public override Type GetChildDataContextType(Type dataContext, DataContextStack controlContextStack, ResolvedControl control, DotvvmProperty property = null)
{
return ReflectionUtils.GetEnumerableType(dataContext);
}
public abstract Type GetChildDataContextType(Type dataContext, DataContextStack controlContextStack, ResolvedControl control, DotvvmProperty property = null);
public static string GetArgsScript(MethodCallExpression expression, DataContextStack dataContext)
{
var target = expression.Object == null ? "null" : JavascriptTranslator.CompileToJavascript(expression.Object, dataContext);
var arguments = new[] { target }.Concat(expression.Arguments.Select(a => JavascriptTranslator.CompileToJavascript(a, dataContext)));
return "[" + String.Join(", ", arguments.Select(a => JsonConvert.SerializeObject(a))) + "]";
}
public Expression Parse(string value, DataContextStack context)
{
return Parse(value, context.DataContextType, context.Parents().ToArray(), context.RootControlType);
}
public override Type GetChildDataContextType(Type dataContext, DataContextStack controlContextStack, ResolvedControl control, DotvvmProperty property = null)
{
return type;
}