08.03-block的类型

1. block的类型

1. 全局block

在data区
没有访问变量
进行了copy操作,依然是__NSGlobalBlock__

		int age = 10;
        //globalBlock
        void (^globalBlock)(void) = ^{
            NSLog(@"------");
        };
        NSLog(@"globalBlock -- %@",globalBlock);
        //ARC :<__NSGlobalBlock__: 0x100004040>
        //MRC : <__NSGlobalBlock__: 0x100004038>
        globalBlock();

• 如果使用了全局变量,也是__NSGlobalBlock__

//stackBlock
        void (^stackBlock)(void) = ^{
            NSLog(@"------%d",globalvari);
        };
        NSLog(@"stackBlock -- %@",stackBlock);
        //ARC : <__NSGlobalBlock__: 0x100004038>
        //MRC : <__NSGlobalBlock__: 0x100004030>
        stackBlock();
        
        //mallocBlock
        void (^mallocBlock)(void) = [^{
            NSLog(@"------%d",globalvari);
        } copy];
        NSLog(@"mallocBlock -- %@",mallocBlock);
        //ARC :<__NSGlobalBlock__: 0x100004058>
        //MRC : <__NSGlobalBlock__: 0x100004050>
        mallocBlock();

---

2. 栈block

在栈区
访问了局部变量
ARC下是__NSMallocBlock__ : ARC下自动进行了copy操作
MRC下才是__NSStackBlock__
进行copy操作,从栈区赋值到堆区

void (^stackBlock)(void) = ^{
	NSLog(@"------%d",age);
};
	NSLog(@"stackBlock -- %@",stackBlock);
//ARC : <__NSMallocBlock__: 0x101066810>
//MRC : <__NSStackBlock__: 0x7ff7bfeff2b0>
	stackBlock();

---

3. 堆block

NSStackBlock 调用了copy
进行copy操作,引用计数+1

void (^mallocBlock)(void) = [^{
            NSLog(@"------%d",age);
        } copy];
        NSLog(@"mallocBlock -- %@",mallocBlock);
        //ARC :<__NSMallocBlock__: 0x101066810>
        //MRC : <__NSMallocBlock__: 0x101105500>
        mallocBlock();

---

2. 总结

MRC环境下