Property paths are strings that describe the location of a property within a container object.
You can use property paths to get or set the data of an object at a specific path or accept a visitor on a sub-property of an object.
Property paths are constructed from strings and resolve a specific property instance from a root object. For example, the path foo.bar.baz[12] resolves the 13th element of the baz list container within the bar container, which is nested inside the foo container.
To create and manipulate property paths, use the Unity.Properties.PropertyPath class.
You can use property paths to do the following:
Unity.Properties.PropertyPath is an immutable struct type. When you construct a property path from a string, allocations occur for sub-string extraction.
The following table lists the allocation behaviors when a property path is constructed from a string:
| 文字列 | Length | Allocations | Allocations reason |
|---|---|---|---|
"Path" |
1 | 0 | Use the string as-is. |
"Path.To" |
2 | 2 | Split the string into two parts. |
"Path.To[2]" |
3 | 3 | Split the string into two parts and extract the index. |
"Path.To[2].My" |
4 | 4 | |
"Path.To[2].My.Value" |
5 | 6 | Allocate an array for the additional parts. |
The following table lists the allocation behaviors when a property path is constructed from parts:
| 文字列 | Length | Allocations | Allocations reason |
|---|---|---|---|
PropertyPath.FromName("Path") |
1 | 0 | |
PropertyPath.AppendName(previous, "To") |
2 | 0 | |
PropertyPath.AppendIndex(previous, 2) |
3 | 0 | |
PropertyPath.AppendName(previous, "My") |
4 | 0 | |
PropertyPath.AppendName(previous, "Value") |
5 | 1 | Allocate an array for the additional parts. |
To optimize performance and avoid allocating memory: