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docs/api/memory/linear-allocator/get-capacity.md

@@ -0,0 +1,33 @@
+# LinearAllocator::GetCapacity
+
+```cpp
+size_t GetCapacity() const;
+```
+
+返回分配器的总容量，即预分配缓冲区的大小。此值在构造时确定，之后保持不变。
+
+**参数：** 无
+
+**返回：** 总容量（字节数）
+
+**复杂度：** O(1)
+
+**示例：**
+
+```cpp
+#include <XCEngine/Memory/LinearAllocator.h>
+
+LinearAllocator allocator(1024 * 1024); // 1MB
+
+size_t capacity = allocator.GetCapacity(); // 1048576
+
+allocator.Allocate(512);
+allocator.Allocate(256);
+
+size_t used = allocator.GetUsedSize();   // 768
+size_t remaining = allocator.GetCapacity() - allocator.GetUsedSize(); // 1047808
+```
+
+## 相关文档
+
+- [LinearAllocator 总览](linear-allocator.md) - 返回类总览