IOS 中runtime使用方法整理

做iOS的朋友都知道或听说runtime,这个东西很像java的反射机制,但功能远胜于java的反射。通过runtime我们可以动态的向一个类中添加属性、成员变量、方法，以及对其进行读写访问。

新建两个类ClassOne和ClassTwo

? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 #import <Foundation/Foundation.h> @interface ClassOne : NSObject{ NSString *_publicVar1; NSString *_publicVar2; } @property(nonatomic,copy) NSString *publicProperty1; @property(nonatomic,copy) NSString *publicProperty2; - (void) testClassOneWithArg1:(NSString *)arg1; @end #import "ClassOne.h" @interface ClassOne() @property(nonatomic,copy) NSString *privateProperty1; @property(nonatomic,copy) NSString *privateProperty2; @end @implementation ClassOne{ NSString *_privateVar1; NSString *_privateVar2; } - (void)testClassOneWithArg1:(NSString *)arg1{ NSLog(@"this is CalssOne, arg1:%@",arg1); } - (void)testClassOneWithArg1:(NSString *)arg1 arg2:arg2{ NSLog(@"this is CalssOne, arg1:%@ arg2:%@",arg1,arg2); } @end ? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 #import <Foundation/Foundation.h> @interface ClassTwo : NSObject - (void) testClassTwoWithArg1:(NSString *)arg1 arg2:(NSString *)arg2; @end #import "ClassTwo.h" @implementation ClassTwo - (void)testClassTwoWithArg1:(NSString *)arg1 arg2:(NSString *)arg2{ NSLog(@"this is ClassTwo arg1:%@,arg2:%@",arg1,arg2); } @end

1.拷贝对象

? 1 2 ClassOne *one = [ClassOne new]; id onec1 = object_copy(one,sizeof(one));

2.给类添加方法

? 1 2 3 4 5 6 7 8 9 ClassOne *one = [ClassOne new]; class_addMethod([ClassOne class], @selector(testClassOneWithArg1:arg2:arg3:), (IMP)testClassOne , "i@:@@@"); [one testClassOneWithArg1:@"arg1" arg2:@"arg2" arg3:@"arg3"]; //方法对应的C函数 int testClassOne(id self,SEL _cmd, NSString *arg1,NSString *arg2,NSString *arg3){ NSLog(@"this is a test function add to ClassOne as a methad with arg1:%@ arg2:%@ and arg3:%@",arg1,arg2,arg3); return 10; }

3.添加属性（方式一）

? 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 //属性类型 objc_property_attribute_t type = { "T", "@\"NSString\"" }; //访问类型 objc_property_attribute_t ownership = { "C", "" }; //对应成员变量名称 objc_property_attribute_t backingivar = { "V", "_testPropertyName" }; objc_property_attribute_t attrs[] = { type, ownership, backingivar }; class_addProperty([ClassOne class], "testPropertyName", attrs, 3); class_addMethod([ClassOne class], @selector(testPropertyName), (IMP)testPropertyNameGetter , "@:@@"); class_addMethod([ClassOne class], @selector(setTestPropertyName:), (IMP)testPropertyNameSetter, "v:@@@"); //属性对应的Getter方法 NSString* testPropertyNameGetter(id self,SEL _cmd){ Ivar ivar = class_getInstanceVariable([ClassOne class], "_testPropertyName"); return object_getIvar(self, ivar); } //属性对应的Setter方法 void testPropertyNameSetter(id self,SEL _cmd,NSString *testPropertyNameValue){ Ivar ivar = class_getInstanceVariable([ClassOne class], "_testPropertyName"); object_setIvar(self, ivar, testPropertyNameValue); }

4.添加属性（方式2）

? 1 2 3 4 ClassOne *one = [ClassOne new]; objc_setAssociatedObject(one, "objTag", @"value", OBJC_ASSOCIATION_COPY); NSString *value = objc_getAssociatedObject(one, "objTag"); NSLog(@"通过Associate设置:%@",value);

5.获取类的名称

? 1 2 3 ClassOne *one = [ClassOne new]; const char *className = object_getClassName(one); NSLog(@"className:%@",[NSString stringWithUTF8String:className]);

6.获取一个类的所有方法

? 1 2 3 4 5 6 7 UInt count; Method *methods = class_copyMethodList([ClassOne class], &count); for (int i = 0; i < count; i++) { Method method = methods[i]; SEL sel = method_getName(method); NSLog(@"方法名:%@",NSStringFromSelector(sel)); }

7.获取一个类的所有属性

? 1 2 3 4 5 6 7 8 9 uint propertyCount; objc_property_t *ps = class_copyPropertyList([ClassOne class], &propertyCount); for (uint i = 0; i < propertyCount; i++) { objc_property_t property = ps[i]; const char *propertyName = property_getName(property); const char *propertyAttributes = property_getAttributes(property); NSLog(@"propertyName:%@",[NSString stringWithUTF8String:propertyName]); NSLog(@"propertyAttributes:%@",[NSString stringWithUTF8String:propertyAttributes]); }

8.获取类的所有成员变量

? 1 2 3 4 5 6 7 uint ivarCount; Ivar *ivars = class_copyIvarList([ClassOne class], &ivarCount); for (uint i = 0; i < ivarCount; i++) { Ivar ivar = ivars[i]; const char *ivarName = ivar_getName(ivar); NSLog(@"ivarName:%@",[NSString stringWithUTF8String:ivarName]); }

9.获得成员变量类型

? 1 2 3 4 5 6 7 8 uint ivarCount; Ivar *ivars = class_copyIvarList([ClassOne class], &ivarCount); for (uint i = 0; i < ivarCount; i++) { Ivar ivar = ivars[i]; const char *ivarName = ivar_getName(ivar); const char *type = ivar_getTypeEncoding(ivar); NSLog(@"ivarName=%@,type=%@",[NSString stringWithUTF8String:ivarName],[NSString stringWithUTF8String:type]); }

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原文链接：http://blog.csdn.net/mr_yong/article/details/50330151