/// <summary>
/// Parses the property.
/// </summary>
/// <returns>The property.</returns>
/// <param name="current">Current.</param>
/// <param name="toReturn">To return.</param>
private static Expression ParseProperty(Expression current, ParsedExpression toReturn)
{
var me = (MemberExpression)current;
toReturn.PrependProperty(me.Member.Name);
current = me.Expression;
return(current);
}
/// <summary>
/// Parse the specified propertyPath.
/// </summary>
/// <param name="propertyPath">Property path.</param>
public static ParsedExpression Parse(LambdaExpression propertyPath)
{
var toReturn = new ParsedExpression();
var current = propertyPath.Body;
while (current != null &&
current.NodeType != ExpressionType.Parameter)
{
current = ParseTo(current, toReturn);
}
return(toReturn);
}
/// <summary>
/// Parses the method call.
/// </summary>
/// <returns>The method call.</returns>
/// <param name="current">Current.</param>
/// <param name="toReturn">To return.</param>
private static Expression ParseMethodCall(Expression current, ParsedExpression toReturn)
{
var me = (MethodCallExpression)current;
if (me.Method.Name != "get_Item" ||
me.Arguments.Count != 1)
{
throw new ArgumentException(
"Property expression must be of the form 'x => x.SomeProperty.SomeOtherProperty' or 'x => x.SomeCollection[0].Property'");
}
var argument = me.Arguments[0];
argument = ConvertMemberAccessToConstant(argument);
toReturn.PrependIndexed(argument.ToString());
current = me.Object;
return(current);
}
/// <summary>
/// Parses to.
/// </summary>
/// <returns>The to.</returns>
/// <param name="current">Current.</param>
/// <param name="toReturn">To return.</param>
private static Expression ParseTo(Expression current, ParsedExpression toReturn)
{
// This happens when a value type gets boxed
if (current.NodeType == ExpressionType.Convert || current.NodeType == ExpressionType.ConvertChecked)
{
return(Unbox(current));
}
if (current.NodeType == ExpressionType.MemberAccess)
{
return(ParseProperty(current, toReturn));
}
if (current is MethodCallExpression)
{
return(ParseMethodCall(current, toReturn));
}
throw new ArgumentException(
"Property expression must be of the form 'x => x.SomeProperty.SomeOtherProperty'");
}