方法调用方式IMP、Selector、NSinvocation

@implementation Person

  • (float)personMethod{

    NSLog(@"\n %s return 5.555 \n",func);

    return 5.00;
    }

  • (float)personMethodWithPara1:(float)para1 para2:(NSString *)para2{

    NSLog(@"\n %s return 5.555 p1:%f...p2:%@ \n",func,para1,para2);

    return 5.99;
    }

  • (NSDictionary *)personMethod2WithPara1:(float)para1 para2:(NSString *)para2{

    NSLog(@"\n %s return 5.555 p1:%f...p2:%@ \n",func,para1,para2);

    return @{@"k":@"kang",@"h":@"hong"};
    }

@end

Person * per = [[Person alloc] init];

// 方法1 performSelector

// [per performSelector:@selector(personMethod)];
// [per performSelector:@selector(personMethodWithPara1: para2:) withObject:@(1.000) withObject:@"abcde"];

// 方法2 IMP

// SEL sel1 = NSSelectorFromString(@"personMethod");
// SEL sel2 = NSSelectorFromString(@"personMethodWithPara1:para2:");
// IMP imp1 = [per methodForSelector:sel1];
// IMP imp2 = [per methodForSelector:sel2];
//
// float (func1)(id , SEL ) = (void)imp1;
// float (*func2)(id , SEL , float , NSString ) = (void)imp2;
//
// float result1 = func1(per , sel1);
// float result2 = func2(per , sel1 , 1.234 , @"one.two..");

// 方法3 invoke

NSArray * paras = @[@(1.234),@"KANGKANG"];
SEL sel = NSSelectorFromString(@"personMethodWithPara1:para2:");
if (!sel) return;
//生成方法签名

// NSMethodSignature *signature = [NSMethodSignature signatureWithObjCTypes:"v@:"];
// # 类方法的方法签名
// NSMethodSignature *signature = [[对象 class] instanceMethodSignatureForSelector:@selector(方法)];
// # 对象方法的方法签名
// NSMethodSignature *signature = [[对象 class] methodSignatureForSelector:@selector(方法)];
// sel可以不是调用函数 但是必须保障参数个数、返回值相同
NSMethodSignature *signature = [per methodSignatureForSelector:sel];
NSInteger parasCount = signature.numberOfArguments;//参数数量

NSInvocation * invocation = [NSInvocation invocationWithMethodSignature:signature];
invocation.target = per;
invocation.selector = sel;
NSInteger argumentCount = MIN(parasCount, paras.count);
for (int i = 0; i< argumentCount; i++) {
    //获取参数类型
    //const char *type = [signature getArgumentTypeAtIndex:2 + i];
    //if (strcmp(type, "@") == 0) { //可以判断参数类型
    id argument = paras[i];
    [invocation setArgument:&argument atIndex:2 + i];
}
[invocation invoke];//调用
//签名判断返回值存在与否
//获得返回值类型
const char *returnType = signature.methodReturnType;
//声明返回值变量
__autoreleasing NSObject *returnValue=nil;
//如果没有返回值，也就是消息声明为void，那么returnValue=nil
if( !strcmp(returnType, @encode(void)) ){
returnValue =  nil;
}
//如果返回值为对象，那么为变量赋值
else if( !strcmp(returnType, @encode(id)) ){
  [invocation getReturnValue:&returnValue];
  NSLog(@"==%@",returnValue);
}
else{
//如果返回值为普通类型NSInteger  BOOL
//返回值长度
NSUInteger length = [signature methodReturnLength];
//根据长度申请内存
void *buffer = (void *)malloc(length);
//为变量赋值
[invocation getReturnValue:buffer];
//
if( !strcmp(returnType, @encode(BOOL)) ) {
returnValue = [NSNumber numberWithBool:*((BOOL*)buffer)];
}
else if( !strcmp(returnType, @encode(NSInteger)) ){
returnValue = [NSNumber numberWithInteger:*((NSInteger*)buffer)];
}
else if( !strcmp(returnType, @encode(float)) ){
returnValue = [NSNumber numberWithFloat:*((float*)buffer)];
}
free(buffer);
}

runtime 获取相关属性方法

@interface MethodOrlvaView : UIView

@property(nonatomic,copy) NSString * properHName;

@property(nonatomic,copy) NSArray * properHArr;

@property(nonatomic,assign) float properHAge;

@end

@interface MethodOrlvaView (){
float innerMivar;
}
@property(nonatomic,copy) NSString * innerMProperName;
@end
@implementation MethodOrlvaView

  • (void)test1{
    NSLog(@"%s",func);
    }
  • (void)test2{
    NSLog(@"%s",func);
    }
  • (float)testFloat{
    NSLog(@"%s",func);
    return 9.99;
    }

@end

@implementation MethodOrIvarGETViewController

  • (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    //获取属性
    [self getPropertyList];
    //获取变量
    [self getIvarList];
    //获取实例方法
    [self getInstanceMethodList];
    //后去类方法
    [self getClassMethodList];
    }

//return 2021-01-21 17:39:27.268583+0800 KKKThread[31423:20666556] ***类方法名:test2

  • (void)getClassMethodList{
    unsigned int count;
    Method methods =class_copyMethodList(object_getClass([MethodOrlvaView class]), &count);
    for (int i =0; i < count; i++) {
    SEL name = method_getName(methods[i]);
    NSLog(@"    **类方法名:%@",NSStringFromSelector(name));
    }
    free(methods);
    }

/**
result
2021-01-21 17:39:27.262748+0800 KKKThread[31423:20666556] ***实例方法名:test1
2021-01-21 17:39:27.262841+0800 KKKThread[31423:20666556] ***实例方法名:testFloat
2021-01-21 17:39:27.263071+0800 KKKThread[31423:20666556] ***实例方法名:properHName
2021-01-21 17:39:27.263255+0800 KKKThread[31423:20666556] ***实例方法名:setProperHName:
2021-01-21 17:39:27.263481+0800 KKKThread[31423:20666556] ***实例方法名:properHArr
2021-01-21 17:39:27.263705+0800 KKKThread[31423:20666556] ***实例方法名:setProperHArr:
2021-01-21 17:39:27.263917+0800 KKKThread[31423:20666556] ***实例方法名:properHAge
2021-01-21 17:39:27.268087+0800 KKKThread[31423:20666556] ***实例方法名:setProperHAge:
2021-01-21 17:39:27.268208+0800 KKKThread[31423:20666556] ***实例方法名:innerMProperName
2021-01-21 17:39:27.268346+0800 KKKThread[31423:20666556] ***实例方法名:setInnerMProperName:
2021-01-21 17:39:27.268453+0800 KKKThread[31423:20666556] ***实例方法名:.cxx_destruct

*/

  • (void)getInstanceMethodList{
    unsigned int count;
    Method methods = class_copyMethodList([MethodOrlvaView class], &count);
    for (int i =0; i < count; i++) {
    SEL name = method_getName(methods[i]);
    NSLog(@"    **实例方法名:%@",NSStringFromSelector(name));
    }
    free(methods);
    }

/**
2021-01-21 17:37:03.310551+0800 KKKThread[31376:20663871] 变量名：innerMivar
2021-01-21 17:37:03.310650+0800 KKKThread[31376:20663871] 变量名：_properHAge
2021-01-21 17:37:03.310739+0800 KKKThread[31376:20663871] 变量名：_properHName
2021-01-21 17:37:03.310814+0800 KKKThread[31376:20663871] 变量名：_properHArr
2021-01-21 17:37:03.310889+0800 KKKThread[31376:20663871] 变量名：_innerMProperName
*/

  • (void)getIvarList{
    unsigned int count ;
    Ivar *ivars = class_copyIvarList(MethodOrlvaView.class, &count);
    for (int i = 0 ; i < count ; i ++) {
    Ivar ivar = ivars[i];
    const char * _Nullable charVar = ivar_getName(ivar);
    NSString * nsString = [NSString stringWithCString:charVar encoding:NSUTF8StringEncoding];
    NSLog(@"变量名：%@",nsString);
    }
    free(ivars);

}
//获取类的属性
/**
return
2021-01-21 17:30:53.636219+0800 KKKThread[31305:20659077] 属性名：innerMProperName
2021-01-21 17:30:53.636375+0800 KKKThread[31305:20659077] 属性名：properHName
2021-01-21 17:30:53.636512+0800 KKKThread[31305:20659077] 属性名：properHArr
2021-01-21 17:30:53.636628+0800 KKKThread[31305:20659077] 属性名：properHAge
*/

  • (void)getPropertyList {
    unsigned int count;
    objc_property_t *propers = class_copyPropertyList([MethodOrlvaView class], &count);
    for (int i = 0 ; i< count ; i++) {
    objc_property_t propert = propers[i];
    const char *name = property_getName(propert);
    NSString *ocName = [NSString stringWithCString:name encoding:NSUTF8StringEncoding];
    NSLog(@"属性名：%@",ocName);
    }
    free(propers);
    }

@end

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