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By Design
Votes
0
Found in
2019.4
2020.3
2020.3.14f1
2021.2
2022.1
Issue ID
1383018
Regression
No
Variable values are not assigned when a Monobehaviour script has a constructor requiring a parameter
Reproduction steps:
1. Open the attached project "Case_1383018" and load Scene "SampleScene"
2. Enter Play Mode
3. Observe the Console
Expected result: "someTestString" is printed in the Console
Actual result: "Null" is printed in the Console
Reproducible with: 2019.4.33f1, 2020.3.23f1, 2021.2.4f1, 2022.1.0a16
Notes:
- Issue is not reproducible when using a parameterless constructor
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Resolution Note (2022.1.X):
This is actually by design:
Instantiation of MonoBheviours is done by the engine in a very special way that can't be customized for performance reasons. One of the effects is that we never call parameterized constructors even if no default constructors exist.
Also default constructors are called in non-totally obvious ways, so users should refrain from declaring constructors on Behaviours at all (see http://ilkinulas.github.io/development/unity/2016/05/30/monobehaviour-constructor.html)