标签：des style blog http color os 文件 io
-(void )test3{ NSString *_person2=@"person2"; NSLog(@"block init:%@,%p,%p",_person2,&_person2,_person2); void (^myBlock)(int) = ^(int num) { NSLog(@"block excuteing:%@,%p,%p",_person2,&_person2,_person2); }; _person2=@"person22"; NSLog(@"block excutebefore:%@,%p,%p",_person2,&_person2,_person2); myBlock(1); NSLog(@"block excuteafter:%@,%p,%p",_person2,&_person2,_person2); }
//这里应该是注册代码中的常量，下面会用到
#define __OFFSETOFIVAR__(TYPE, MEMBER) ((long long) &((TYPE *)0)->MEMBER) static __NSConstantStringImpl __NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_0 __attribute__ ((section ("__DATA, __cfstring"))) = {__CFConstantStringClassReference,0x000007c8,"KDBlockTest dealloc",19}; static __NSConstantStringImpl __NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_1 __attribute__ ((section ("__DATA, __cfstring"))) = {__CFConstantStringClassReference,0x000007c8,"person2",7}; static __NSConstantStringImpl __NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_2 __attribute__ ((section ("__DATA, __cfstring"))) = {__CFConstantStringClassReference,0x000007c8,"block init:%@,%p,%p",19}; static __NSConstantStringImpl __NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_3 __attribute__ ((section ("__DATA, __cfstring"))) = {__CFConstantStringClassReference,0x000007c8,"block excuteing:%@,%p,%p",24}; static __NSConstantStringImpl __NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_4 __attribute__ ((section ("__DATA, __cfstring"))) = {__CFConstantStringClassReference,0x000007c8,"person22",8}; static __NSConstantStringImpl __NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_5 __attribute__ ((section ("__DATA, __cfstring"))) = {__CFConstantStringClassReference,0x000007c8,"block excutebefore:%@,%p,%p",27}; static __NSConstantStringImpl __NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_6 __attribute__ ((section ("__DATA, __cfstring"))) = {__CFConstantStringClassReference,0x000007c8,"block excuteafter:%@,%p,%p",26};
struct __KDBlockTest__test3_block_impl_0 { struct __block_impl impl; struct __KDBlockTest__test3_block_desc_0* Desc; NSString *_person2; __KDBlockTest__test3_block_impl_0(void *fp, struct __KDBlockTest__test3_block_desc_0 *desc, NSString *__person2, int flags=0) : _person2(__person2) { impl.isa = &_NSConcreteStackBlock; impl.Flags = flags; impl.FuncPtr = fp; Desc = desc; }
//block实现的函数
static void __KDBlockTest__test3_block_func_0(struct __KDBlockTest__test3_block_impl_0 *__cself, int num) { NSString *_person2 = __cself->_person2; // bound by copy NSLog((NSString *)&__NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_3,_person2,&_person2,_person2); }
//copy函数，可以拷贝到堆上
static void __KDBlockTest__test3_block_copy_0(struct __KDBlockTest__test3_block_impl_0*dst, struct __KDBlockTest__test3_block_impl_0*src) {_Block_object_assign((void*)&dst->_person2, (void*)src->_person2, 3/*BLOCK_FIELD_IS_OBJECT*/);}
//对应的释放函数
static void __KDBlockTest__test3_block_dispose_0(struct __KDBlockTest__test3_block_impl_0*src) {_Block_object_dispose((void*)src->_person2, 3/*BLOCK_FIELD_IS_OBJECT*/);}
//block对象的描述信息（大小等等）
static struct __KDBlockTest__test3_block_desc_0 { size_t reserved; size_t Block_size; void (*copy)(struct __KDBlockTest__test3_block_impl_0*, struct __KDBlockTest__test3_block_impl_0*); void (*dispose)(struct __KDBlockTest__test3_block_impl_0*); } __KDBlockTest__test3_block_desc_0_DATA = { 0, sizeof(struct __KDBlockTest__test3_block_impl_0), __KDBlockTest__test3_block_copy_0, __KDBlockTest__test3_block_dispose_0};
//这是objc测试函数test
static void _I_KDBlockTest_test3(KDBlockTest * self, SEL _cmd) { NSString *_person2=(NSString *)&__NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_1; NSLog((NSString *)&__NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_2,_person2,&_person2,_person2); void (*myBlock)(int) = (void (*)(int))&__KDBlockTest__test3_block_impl_0((void *)__KDBlockTest__test3_block_func_0, &__KDBlockTest__test3_block_desc_0_DATA, _person2, 570425344); _person2=(NSString *)&__NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_4; NSLog((NSString *)&__NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_5,_person2,&_person2,_person2); ((void (*)(__block_impl *, int))((__block_impl *)myBlock)->FuncPtr)((__block_impl *)myBlock, 1); NSLog((NSString *)&__NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_6,_person2,&_person2,_person2); }
__KDBlockTest__test3_block_impl_0(void *fp, struct __KDBlockTest__test3_block_desc_0 *desc, NSString *__person2, int flags=0) : _person2(__person2) { impl.isa = &_NSConcreteStackBlock; impl.Flags = flags; impl.FuncPtr = fp; Desc = desc; }
void (*myBlock)(int) = (void (*)(int))&__KDBlockTest__test3_block_impl_0((void *)__KDBlockTest__test3_block_func_0, &__KDBlockTest__test3_block_desc_0_DATA, _person2, 570425344);
((void (*)(__block_impl *, int))((__block_impl *)myBlock)->FuncPtr)((__block_impl *)myBlock, 1);
其实还是调用了block函数指针 所指向的函数__KDBlockTest__test3_block_func_0，并把block自己作为参数传递进去。
static void __KDBlockTest__test3_block_func_0(struct __KDBlockTest__test3_block_impl_0 *__cself, int num) { NSString *_person2 = __cself->_person2; // bound by copy NSLog((NSString *)&__NSConstantStringImpl__var_folders_5l_2l25j3tn0wl_3zy1hpsq1rhc0000gp_T_KDBlockTest_51f509_mi_3,_person2,&_person2,_person2); }
值得注意的的是，我们在执行之前对_person2修改，但是并没有对block内部产生影响，因为在构造block的时候，block内部对截获的变量已经做了深拷贝，执行block的时候，直接调用函数__KDBlockTest__test3_block_func_0，函数内部，是引用了block拷贝的_person2对象，我想这应该就是block截获变量的特性
标签：des style blog http color os 文件 io
原文地址：http://www.cnblogs.com/NarutoYq/p/3867907.html
