protected override Expression VisitMethodCall(MethodCallExpression m) { if (m.Method.DeclaringType == typeof(String) && m.Method.Name == "StartsWith") { if (ExpressionTreeHelpers.IsSpecificMemberExpression(m.Object, typeof(Place), "Name") || ExpressionTreeHelpers.IsSpecificMemberExpression(m.Object, typeof(Place), "State")) { locations.Add(ExpressionTreeHelpers.GetValueFromExpression(m.Arguments[0])); return(m); } } else if (m.Method.Name == "Contains") { Expression valuesExpression = null; if (m.Method.DeclaringType == typeof(Enumerable)) { if (ExpressionTreeHelpers.IsSpecificMemberExpression(m.Arguments[1], typeof(Place), "Name") || ExpressionTreeHelpers.IsSpecificMemberExpression(m.Arguments[1], typeof(Place), "State")) { valuesExpression = m.Arguments[0]; } } else if (m.Method.DeclaringType == typeof(List <string>)) { if (ExpressionTreeHelpers.IsSpecificMemberExpression(m.Arguments[0], typeof(Place), "Name") || ExpressionTreeHelpers.IsSpecificMemberExpression(m.Arguments[0], typeof(Place), "State")) { valuesExpression = m.Object; } } if (valuesExpression == null || valuesExpression.NodeType != ExpressionType.Constant) { throw new Exception("Could not find the location values."); } ConstantExpression ce = (ConstantExpression)valuesExpression; IEnumerable <string> placeStrings = (IEnumerable <string>)ce.Value; // Add each string in the collection to the list of locations to obtain data about. foreach (string place in placeStrings) { locations.Add(place); } return(m); } return(base.VisitMethodCall(m)); }
internal static bool IsMemberEqualsValueExpression(Expression exp, Type declaringType, string memberName) { if (exp.NodeType != ExpressionType.Equal) { return(false); } var be = (BinaryExpression)exp; // Assert. if (ExpressionTreeHelpers.IsSpecificMemberExpression(be.Left, declaringType, memberName) && ExpressionTreeHelpers.IsSpecificMemberExpression(be.Right, declaringType, memberName)) { throw new Exception("Cannot have 'member' == 'member' in an expression!"); } return(ExpressionTreeHelpers.IsSpecificMemberExpression(be.Left, declaringType, memberName) || ExpressionTreeHelpers.IsSpecificMemberExpression(be.Right, declaringType, memberName)); }