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iOS进阶：Objective-C runtime（一）

第一次看到runtime时，觉得太高大上，动态获取方法、属性等简直厉害的不要不要的。在经过查找资料+实践后，发现runtime并没有想象中那么复杂，接下来对runtime进行基本的介绍。

要使用运行时方法需要引入runtime.h文件

一、基础知识

Method ：成员方法

Ivar : 成员变量

二、常用方法

class_copyPropertyList : 获取属性列表

class_copyMethodList : 获取成员方法列表

class_copyIvarList：获取成员变量列表

ivar_getName：获取变量名

property_getName：获取属性名

使用示例：

1.获取成员变量列表

//1.获取变量list unsigned int ivarCount = 0; //成员变量数 Ivar *ivarList = class_copyIvarList([self class], &ivarCount);//ivar数组 for (int i = 0; i < ivarCount; i++) {//遍历  Ivar ivar = ivarList[i]; //获取ivar  const char *name = ivar_getName(ivar);//获取变量名  NSString *key = [NSString stringWithUTF8String:name];  NSLog(@"%@", key); }

   free(ivarList);

2.获取属性列表

unsigned int count = 0;  objc_property_t *propertList = class_copyPropertyList([self class], &count);  for (int i = 0; i < count; i++) {   objc_property_t property = propertList[i];   const char *name = property_getName(property);   const char *attrs = property_getAttributes(property); //  property_copyAttributeValue(,) 第一个参数为objc_property_t,第二个参数"V"获取变量名,"T"获取类型   const char *value = property_copyAttributeValue(property, "V");   NSLog(@"name = %s, attrs = %s, value = %s", name, attrs, value);  }

free(propertList);

3.获取方法列表

unsigned int count = 0; Method *methodList = class_copyMethodList([self class], &count); for (int i = 0 ; i < count; i++) {  Method method = methodList[i];  SEL selector = method_getName(method);//方法入口  const char *sel_name = sel_getName(selector);  NSLog(@"方法名 %s", sel_name); } free(methodList);

三、使用方向：归档、字典<---->模型、框架封装等

实现归档

#define WKCodingImplementing / - (void)encodeWithCoder:(NSCoder *)aCoder / { /  unsigned int ivarCount = 0; /  Ivar *ivarList = class_copyIvarList([self class], &ivarCount); /  for (int i = 0; i < ivarCount; i++) { /   Ivar ivar = ivarList[i]; /   const char *name = ivar_getName(ivar); /   const char *type = ivar_getTypeEncoding(ivar); /   NSLog(@"%s-----%s", name, type); /   NSString *key = [NSString stringWithUTF8String:name]; /   id value = [self valueForKey:key]; /   [aCoder encodeObject:value forKey:key]; /  } /  free(ivarList); / } / - (nullable instancetype)initWithCoder:(NSCoder *)aDecoder / { /  if (self = [super init]) { /   unsigned int ivarCount = 0; /   Ivar *ivarList = class_copyIvarList([self class], &ivarCount); /   for (int i = 0; i < ivarCount; i++) { /    Ivar ivar = ivarList[i]; /    const char *name = ivar_getName(ivar); /    NSString *key = [NSString stringWithUTF8String:name]; /    NSLog(@"%@ %@", key, value); /    id value = [aDecoder decodeObjectForKey:key]; /    [self setValue:value forKey:key]; /   } /  } /  return self; / }