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03-UnrealEngine/Gameplay/UObject/UnrealSpecifiers/Specifier/UPROPERTY/Blueprint/BlueprintReadWrite/BlueprintReadWrite.md

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+# BlueprintReadWrite
+
+- **功能描述：** 可从蓝图读取或写入此属性。
+
+- **元数据类型：** bool
+- **引擎模块：** Blueprint
+- **作用机制：** 在PropertyFlags中加入[CPF_BlueprintVisible](../../../../Flags/EPropertyFlags/CPF_BlueprintVisible.md)
+- **常用程度：** ★★★★★
+
+可从蓝图读取或写入此属性。
+
+此说明符与 BlueprintReadOnly 说明符不兼容。
+
+## 示例代码：
+
+```cpp
+public:
+	//PropertyFlags:	CPF_BlueprintVisible | CPF_ZeroConstructor | CPF_IsPlainOldData | CPF_NoDestructor | CPF_HasGetValueTypeHash | CPF_NativeAccessSpecifierPublic 
+	UPROPERTY(BlueprintReadWrite, Category = Blueprint)
+		int32 MyInt_ReadWrite = 123;
+	//PropertyFlags:	CPF_BlueprintVisible | CPF_BlueprintReadOnly | CPF_ZeroConstructor | CPF_IsPlainOldData | CPF_NoDestructor | CPF_HasGetValueTypeHash | CPF_NativeAccessSpecifierPublic 
+	UPROPERTY(BlueprintReadOnly, Category = Blueprint)
+		int32 MyInt_ReadOnly = 123;
+```
+
+## 示例效果：
+
+蓝图中可读写：
+
+![Untitled](Untitled.png)
+
+## 原理：
+
+如果有CPF_Edit | CPF_BlueprintVisible | CPF_BlueprintAssignable之一，则可以Get属性。
+
+```cpp
+EPropertyAccessResultFlags PropertyAccessUtil::CanGetPropertyValue(const FProperty* InProp)
+{
+	if (!InProp->HasAnyPropertyFlags(CPF_Edit | CPF_BlueprintVisible | CPF_BlueprintAssignable))
+	{
+		return EPropertyAccessResultFlags::PermissionDenied | EPropertyAccessResultFlags::AccessProtected;
+	}
+
+	return EPropertyAccessResultFlags::Success;
+}
+
+```