ue蓝图节点 for each loop和for loop有什么区别

在Unreal Engine（UE4）的蓝图系统中，`For Each Loop` 和 `For Loop` 都用于遍历数组或其他迭代数据结构，但它们之间有一些关键的区别：

1. **For Loop**：这是一个通用的循环结构，它接受一个整数变量作为索引，并在每次迭代时递增这个变量。用户需要手动指定开始和结束条件，例如：

   For (int i = 0; i < Array.Length; ++i)
   {
       // 对Array[i]进行操作
   }

这种循环适合当你确切地知道将迭代多少次。

2. **For Each Loop**：更方便，尤其是处理动态集合（如 TArray、ActorArray等）时，它自动处理遍历过程，不需要预先确定迭代次数。例如：

   For Each (const TSubclassOf<AActor> Class in Actors)
   {
       // 对Class实例进行操作
   }

这种循环会逐个取出集合中的元素并执行相应的节点，直到集合为空。

简而言之，`For Loop`需要明确的计数范围，而`For Each Loop`则适用于需要对每个元素进行操作的情况，无需关心内部细节或元素数量。

相关问题

UE4For each loop

In UE4, a "for each" loop is a type of loop that iterates through a collection of objects and performs a set of actions on each object in the collection. The loop can be used to perform a variety of tasks, such as updating the properties of each object, executing a certain function for each object, or checking certain conditions for each object.

The syntax for a for each loop in UE4 is as follows:

for each (Object in Collection)
{
    // Perform actions on Object
}

Here, "Object" is a variable that represents each object in the collection, and "Collection" is the collection of objects that the loop is iterating through. The actions to be performed on each object are placed inside the braces.

For example, let's say we have a collection of actors in our level, and we want to set the visibility of each actor to false. We can use a for each loop to accomplish this:

for each (AActor* Actor in Actors)
{
    Actor->SetActorHiddenInGame(true);
}

Here, "AActor" is the type of object we're iterating through, "Actor" is the variable that represents each actor in the loop, and "Actors" is the collection of actors we're iterating through. The loop sets the "Hidden In Game" property of each actor to true, effectively hiding them from view.

ue4 for each loop的用法

UE4中的For Each Loop可以遍历一个数组或集合中的每个元素，并执行指定的操作。示例如下：

TArray<int32> Numbers = {1, 2, 3, 4, 5};

for (const int32& Number : Numbers)
{
    UE_LOG(LogTemp, Warning, TEXT("Number: %d"), Number);
}

该示例将打印出以下日志：

Number: 1
Number: 2
Number: 3
Number: 4
Number: 5

在For Each Loop中，const int32& Number是迭代器，用于指向当前遍历的元素。您可以使用Number访问每个元素的值，并执行您想要的操作。