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docs/api/core/event/Subscribe.md

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+# Event::Subscribe
+
+```cpp
+uint64_t Subscribe(Callback callback);
+```
+
+订阅事件回调。
+
+**描述**
+
+将回调函数添加到事件订阅列表中，并返回一个唯一的订阅 ID。该 ID 可用于后续退订。线程安全，可在任意线程调用。
+
+**参数：**
+- `callback` - 要订阅的回调函数，类型为 `std::function<void(Args...)>`
+
+**返回：** `uint64_t` - 订阅 ID，用于退订
+
+**复杂度：** O(1) amortized
+
+**示例：**
+
+```cpp
+#include <XCEngine/Core/Event.h>
+
+using namespace XCEngine::Core;
+
+// 定义事件
+Event<int, float> damageEvent;
+
+// 订阅多个回调
+uint64_t id1 = damageEvent.Subscribe([](int damage, float time) {
+    printf("Damage taken: %d at time %f\n", damage, time);
+});
+
+uint64_t id2 = damageEvent.Subscribe([](int damage, float time) {
+    // 记录伤害日志
+});
+
+// 使用 lambda 表达式
+auto callback = [](int damage, float time) {
+    // 处理伤害
+};
+uint64_t id3 = damageEvent.Subscribe(callback);
+```
+
+## 相关文档
+
+- [Event 总览](event.md) - 返回类总览
+- [Unsubscribe](Unsubscribe.md) - 退订事件
+- [Invoke](Invoke.md) - 触发事件