// Static Methods
#region Parse (Expression)
/// <summary>
/// Parse an instance of <see cref="BinaryExpression"/> object.
/// </summary>
/// <typeparam name="TEntity">The target entity type</typeparam>
/// <param name="expression">The instance of <see cref="BinaryExpression"/> to be parsed.</param>
/// <returns>An instance of <see cref="QueryField"/> object.</returns>
internal static QueryField Parse <TEntity>(BinaryExpression expression) where TEntity : class
{
// Only support the following expression type
if (expression.IsExtractable() == false)
{
throw new NotSupportedException($"Expression '{expression.ToString()}' is currently not supported.");
}
// Name
var fieldName = expression.GetName();
if (PropertyCache.Get <TEntity>(Command.None).Any(property => property.PropertyInfo.Name == fieldName) == false)
{
throw new InvalidQueryExpressionException($"Invalid expression '{expression.ToString()}'. The property {fieldName} is not defined on a target type '{typeof(TEntity).FullName}'.");
}
// Value
var value = expression.GetValue();
// Operation
var operation = GetOperation(expression.NodeType);
// Return the value
return(new QueryField(fieldName, operation, value));
}
/// <summary>
/// Parses a property from the data entity object based on the given <see cref="BinaryExpression"/> and converts the result
/// to <see cref="OrderField"/> object.
/// </summary>
/// <typeparam name="TEntity">The type of the data entity that contains the property to be parsed.</typeparam>
/// <param name="expression">The expression to be parsed.</param>
/// <param name="order">The order of the property.</param>
/// <returns>An instance of <see cref="OrderField"/> object.</returns>
internal static OrderField Parse <TEntity>(BinaryExpression expression,
Order order)
where TEntity : class =>
new OrderField(expression.GetName(), order);
/// <summary>
/// Parses a property from the data entity object based on the given <see cref="BinaryExpression"/> and converts the result
/// to <see cref="Field"/> object.
/// </summary>
/// <typeparam name="TEntity">The type of the data entity that contains the property to be parsed.</typeparam>
/// <param name="expression">The expression to be parsed.</param>
/// <returns>An enumerable list of <see cref="Field"/> objects.</returns>
internal static IEnumerable <Field> Parse <TEntity>(BinaryExpression expression)
where TEntity : class =>
(new Field(expression.GetName())).AsEnumerable();
/// <summary>
/// Parses a property from the data entity object based on the given <see cref="BinaryExpression"/> and converts the result
/// to <see cref="Field"/> object.
/// </summary>
/// <typeparam name="TEntity">The type of the data entity that contains the property to be parsed.</typeparam>
/// <param name="expression">The expression to be parsed.</param>
/// <returns>An instance of <see cref="OrderField"/> object.</returns>
internal static Field Parse <TEntity>(BinaryExpression expression)
where TEntity : class
{
return(new Field(expression.GetName()));
}