官方文档学习TArray数组的运算符

 三.运算符

就是我们常说的深拷贝，完全复制一个对象到另一个数组。

MoveTemp的实现原理，应该先进行了深拷贝。再将原动态数组清空。

1.重载== 运算符

元素自身要有 == 。数组要顺序数量同时相同，才能叫数组间的相同。

最后敲一遍实例代码，会有更深的理解。

void AWXArrayActor::OperateArray()
{
	TArray<int32> ValArr3;
	ValArr3.Add(1);
	ValArr3.Add(2);
	ValArr3.Add(3);

	auto ValArr4 = ValArr3;
	// ValArr4 == [1,2,3];
	ValArr4[0] = 5;
	// ValArr3 == [1,2,3];
	// ValArr4 == [5,2,3];

	TArray<int> SValArr3 = MoveTemp(ValArr4);

	// ValArr3 == [5,2,3,1,2,3]
	// ValArr4 == []

	ValArr4 += ValArr3;
	// ValArr4 == [5,2,3,1,2,3]

	TArray<int32> ValArr5 = ValArr3;
	TArray<int32> ValArr6;
	ValArr6 += ValArr4;
	ValArr6.Append(ValArr3);
	TArray<int32> ValArr7 = {1,1,1};
	ValArr7 = MoveTemp(ValArr6);
}

void AWXArrayActor::OperateStrArray()
{
	TArray<FString> FlavorArr1;
	FlavorArr1.Emplace(TEXT("Chocolate"));
	FlavorArr1.Emplace(TEXT("Vanilla"));
	// FlavorArr1 == ["Chocolate","Vanilla"]

	auto FlavorArr2 = FlavorArr1;
	// FlavorArr2 == ["Chocolate","Vanilla"]

	bool bComparison1 = FlavorArr1 == FlavorArr2;
	// bComparison1 == true

	for (auto& Str : FlavorArr2)
	{
		Str = Str.ToUpper();
	}
	// FlavorArr2 == ["CHOCOLATE","VANILLA"]

	bool bComparison2 = FlavorArr1 == FlavorArr2;
	// bComparison2 == true, because FString comparison ignores case

	Exchange(FlavorArr2[0], FlavorArr2[1]);
	// FlavorArr2 == ["VANILLA","CHOCOLATE"]

	bool bComparison3 = FlavorArr1 == FlavorArr2;
	// bComparison3 == false, because the order has changed
}