Find Component

Unreal 

APlayerChar::APlayerChar()

{

  // Set this character to call Tick() every frame.  You can turn this off to improve performance if you don't need it.

PrimaryActorTick.bCanEverTick = true;

                //UStaticMeshComponent* ObstacleMesh = Cast<UStaticMeshComponent>(GetDefaultSubobjectByName(TEXT("Obstacle Mesh")));//Remember : Name was match with Blueprint otherwise crash ue4

//but Error When Use this Function like ObstacleMesh->SetHiddenInGame(true);

                USkeletalMeshComponent* PlayerMesh = GetPawn()->FindComponentByClass<USkeletalMeshComponent>();

                UCapsuleComponent* plyrCapsul = this->GetCapsuleComponent();

}

Unity

[SerializeField] CapsuleCollider plyrCapsul;

void Start() => plyrCapsul = this.gameObject.GetComponent<CapsuleCollider>();