demo https://github.com/ZOYOOPlus/runtime2
//
// ViewController.m
// runtime
// Copyright © 2017年 四海八荒. All rights reserved.
//
#import "ViewController.h"
#import "MyObject.h"
#import "UIView+TYView.h"
#import <objc/runtime.h>
@interface ViewController ()
@end
@implementation ViewController
- (void)viewDidLoad {// 1.类相关函数
// 得到类名 ViewController
NSLog(@"%s",class_getName([self class]));
// 父类类名
// This is superClass 0x10f426da0 isa指针地址
NSLog(@"This is superClass %p",class_getSuperclass([self class]));
// 是否是元类
// Is MateClass 0
NSLog(@"Is MateClass %d",class_isMetaClass([self class]));
// 实例变量大小
// 848
size_t a = class_getInstanceSize([self class]);
NSLog(@"%ld",a);
unsigned int outCount = 0;
MyObject *objtect = [[MyObject alloc] init];
Class cls = objtect.class;
//类名
NSLog(@"Class name %s",class_getName(cls));
//父类名字
NSLog(@"SuperClass name %s",class_getName(class_getSuperclass(cls)));
//是否元类
NSLog(@"Is MetaClass %@",(class_isMetaClass(cls))?@"":@"NOT");
//变量大小
NSLog(@"MyObject size %ld",class_getInstanceSize(cls));
//变量信息
Ivar string = class_getInstanceVariable(cls, "_string");
if (string != NULL) {
NSLog(@"MyObject instance messge %s",ivar_getName(string));
}
// 属性操作
objc_property_t *v = class_copyPropertyList(cls, &outCount);
for (NSInteger i = 0; i< outCount; i++) {
objc_property_t property = v[i];
NSLog(@"property is %s ",property_getName(property));
}
free(v);
//成员变量
Ivar *vars = class_copyIvarList(cls, &outCount);
for (NSInteger i =0; i< outCount; i++) {
Ivar ivar = vars[i];
NSLog(@"copyIvarList is %s is %ld",ivar_getName(ivar),i);
}
free(vars);
//方法操作
Method *methods = class_copyMethodList(cls, &outCount);
for (NSInteger i =0; i< outCount; i++) {
Method met = methods[i];
#pragma clang diagnostic ignored"-Wformat"
NSLog(@"Method is %s",method_getName(met));
}
free(methods);
// Format specifies type 'char *' but the argument has type 'SEL _Nonnull'
// 获取方法名
Method method = class_getInstanceMethod(cls,@selector(method1));
NSLog(@"Method name is %s",method_getName(method));
// 判断方法是否存在
#pragma clang diagnostic ignored"-Wundeclared-selector"
NSLog(@"Have you method %d",class_respondsToSelector(cls, @selector(method3WithArge1:arge2:)));
// 指向函数实现的指针，相当于方法的实现
IMP imp = class_getMethodImplementation(cls, @selector(method1));
imp();
//动态创建类
#pragma clang diagnostic ignored" -Wunused-variable"
// 注:运行时规定,只能在objc_allocateClassPair与objc_registerClassPair两个函数之间为类添加变量
// 1.添加一个自定义的类 类名是MySubClass
// 父类class,类名,额外空间
Class myClass = objc_allocateClassPair(objtect.class, "MySubClass", 0);
// 2.增加方法，交换方法
//注: v@: 意思是 v是void @:没有返回参数
if( class_addMethod(myClass, @selector(mysubMethod1),(IMP)mysubMethod1, "v@:")){
class_replaceMethod(myClass, @selector(method1), (IMP)mysubMethod1,"v@:");
}
/*
3.增加一个NSSsting类型属性 属性名myString
变量size sizeof(NSString)
对齐 指针类型的为log2(sizeof(NSString*))
类型 @encode(NSString*)
class_addIvar(class,变量名,变量size,对齐,类型)
*/
//添加同名属性会失败
BOOL isd = class_addIvar(myClass, "_myString", sizeof(NSString *), log(sizeof(NSString *)), @encode(NSString *));
NSLog(@"属性是否添加成功 %d",isd);
/*
特性相关编码
属性的特性字符串 以 T@encode(type) 开头, 以 V实例变量名称 结尾,中间以特性编码填充,通过property_getAttributes即可查看
特性编码 具体含义
R readonly
C copy
& retain ARC strong
N nonatomic
G(name) getter=(name)
S(name) setter=(name)
D @dynamic
W weak
P 用于垃圾回收机制
*/
//@T
objc_property_attribute_t type;
type.name = "T";
type.value = @encode(NSString *);
//copy
objc_property_attribute_t owership = {"C",""};
//nonatomic
objc_property_attribute_t oeership2 = {"N",""};
//V_属性名
objc_property_attribute_t var = {"V","_myString"};
//特性数组
objc_property_attribute_t attributes[] = {type,owership,oeership2,var};
//向类中添加名为myString的属性,属性的特性包含在attributes中
class_addProperty(myClass, "myString", attributes, 4);
unsigned int propertyCount;
objc_property_t * properties = class_copyPropertyList(myClass, &propertyCount);
for (int i = 0; i<propertyCount; i++) {
NSLog(@"属性的名称为 : %s",property_getName(properties[i]));
NSLog(@"属性的特性字符串为: %s",property_getAttributes(properties[i]));
}
//释放属性列表数组
free(properties);
//在应用中注册由objc_allocateClassPair创建的类
objc_registerClassPair(myClass);
id instance = [[myClass alloc] init];
[instance performSelector:@selector(mysubMethod1)];
[instance performSelector:@selector(method1)];
// 销毁一个类及相关联的类
// 不过需要注意的是，如果程序运行中还存在类或其子类的实例，则不能调用针对类调用该方法
//objc_disposeClassPair(myClass);
//关联对象
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(100, 100, 100, 100)];
view.backgroundColor = [UIColor redColor];
[view setTapActionWithBlock:^{
NSLog(@"saAS");
}];
[self.view addSubview:view];
// SEL
// Objective-C在编译时，会依据每一个方法的名字、参数序列，生成一个唯一的整型标识(Int类型的地址)，这个标识就是SEL
// SEL只是一个指向方法的指针（准确的说，只是一个根据方法名hash化了的KEY值，能唯一代表一个方法
// 而对于字符串的比较仅仅需要比较他们的地址就可以了，可以说速度上无语伦比
// sel : 0x104dd7735
/*
三种方法来获取SEL:
sel_registerName函数
Objective-C编译器提供的@selector()
NSSelectorFromString()方法
*/
SEL sel1 = @selector(method1);
NSLog(@"sel : %p", sel1);
}
static void mysubMethod1(id self,SEL _cmd){
NSLog(@"这是添加的方法");
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end
增加中，可先看demo