ds_list_find_value(id, pos);
| 参数 | 描述 |
|---|---|
| id | The id of the list to use. |
| pos | The position to look at, where 0 corresponds to the very beginning of the list and the final position is ds_list_size(id)-1. |
Returns: Real, String or Undefined
With this function you can check the given list position and the
value held within the list for that position will be returned. Note
that if you give a position that is outside of the given list size
(ie: position 11 in a 10 value list) then the function may return
undefined or 0. This is because when you create the
list, internally the first few entries in the list are set to 0 to
minimize performance issues when initially adding items to the list
(although the ds_list_size() function will still
return 0 on a newly created list). If you wish to ensure that the
list is "truly" empty on create, then you should call ds_list_clear() after creating
the list, which will then mean that any values returned for
unpopulated list slots will be undefined, which you can
then check consistently using the
is_undefined() function.
val = ds_list_find_value(list, ds_list_size(list) - 1);
The above code checks the list indexed in the variable "list" at the last position in the list and stores the returned value in the variable "val".