/// <summary>
/// Evaluates the binding.
/// </summary>
internal object EvaluateBinding(ExpressionEvaluationVisitor visitor, string expression, string pathExpression)
{
// parse
var node = ParseBinding(expression);
var result = visitor.Visit(node);
visitor.BackupCurrentPosition(result, pathExpression);
return result;
}
/// <summary>
/// Resolves the path in the view model and returns the target object.
/// </summary>
private List<object> ResolveViewModelPath(object viewModel, RedwoodControl viewRootControl, string[] path)
{
var visitor = new ExpressionEvaluationVisitor(viewModel, viewRootControl);
var outputHierarchy = new List<object>();
outputHierarchy.Add(viewModel);
foreach (var expression in path)
{
// evaluate path fragment
var pathTree = CSharpSyntaxTree.ParseText(expression, new CSharpParseOptions(LanguageVersion.CSharp5, DocumentationMode.Parse, SourceCodeKind.Interactive));
var pathExpr = pathTree.EnsureSingleExpression();
var result = visitor.Visit(pathExpr);
visitor.BackupCurrentPosition(result, expression);
outputHierarchy.Add(result);
}
return outputHierarchy;
}
/// <summary>
/// Finds the method on view model.
/// </summary>
private static MethodInfo FindMethodOnViewModel(object viewModel, RedwoodControl viewRootControl, List<object> hierarchy, InvocationExpressionSyntax node, out object target)
{
MethodInfo method;
var methodEvaluator = new ExpressionEvaluationVisitor(viewModel, viewRootControl, hierarchy)
{
AllowMethods = true
};
method = methodEvaluator.Visit(node.Expression) as MethodInfo;
if (method == null)
{
throw new Exception("The command path was not found!");
}
target = methodEvaluator.MethodInvocationTarget;
return method;
}
/// <summary>
/// Evaluates the expression the on view model with specified hierarchy.
/// </summary>
private object EvaluateOnViewModel(object viewModel, RedwoodControl viewRootControl, List<object> hierarchy, string expression)
{
var pathTree = CSharpSyntaxTree.ParseText(expression, new CSharpParseOptions(LanguageVersion.CSharp5, DocumentationMode.Parse, SourceCodeKind.Interactive));
var pathExpr = pathTree.EnsureSingleExpression();
var visitor = new ExpressionEvaluationVisitor(viewModel, viewRootControl, hierarchy);
return visitor.Visit(pathExpr);
}
/// <summary>
/// Evaluates the command arguments.
/// </summary>
private static object[] EvaluateCommandArguments(object viewModel, RedwoodControl viewRootControl, List<object> hierarchy, InvocationExpressionSyntax node)
{
var arguments = node.ArgumentList.Arguments.Select(a =>
{
var evaluator = new ExpressionEvaluationVisitor(viewModel, viewRootControl, hierarchy);
return evaluator.Visit(a);
}).ToArray();
return arguments;
}