在Objective-C中獲取對象屬性列表

Question

如何在Objective-C中獲得給定對象屬性的列表（以NSArray或NSDictionary的形式）？

設想以下情形：我定義了一個父類，該類僅擴展了NSObject ，該類包含一個NSString ，一個BOOL和一個NSData對象作為屬性。 然后，我有幾個擴展該父類的類，每個類都添加了許多不同的屬性。

我有什么辦法可以在父類上實現遍歷整個對象並返回例如每個（子）類屬性的NSArray作為不在父類上的NSStrings的實例方法，因此我以后可以將這些NSString用於KVC？

Answer 1

我只是設法自己得到答案。 通過使用Obj-C運行時庫，我可以按自己的方式訪問屬性：

- (void)myMethod {
    unsigned int outCount, i;
    objc_property_t *properties = class_copyPropertyList([self class], &outCount);
    for(i = 0; i < outCount; i++) {
        objc_property_t property = properties[i];
        const char *propName = property_getName(property);
        if(propName) {
            const char *propType = getPropertyType(property);
            NSString *propertyName = [NSString stringWithCString:propName
                                                                encoding:[NSString defaultCStringEncoding]];
            NSString *propertyType = [NSString stringWithCString:propType
                                                                encoding:[NSString defaultCStringEncoding]];
            ...
        }
    }
    free(properties);
}

這需要我創建一個“ getPropertyType” C函數，該函數主要取自Apple代碼示例（目前不記得確切的源代碼）：

static const char *getPropertyType(objc_property_t property) {
    const char *attributes = property_getAttributes(property);
    char buffer[1 + strlen(attributes)];
    strcpy(buffer, attributes);
    char *state = buffer, *attribute;
    while ((attribute = strsep(&state, ",")) != NULL) {
        if (attribute[0] == 'T') {
            if (strlen(attribute) <= 4) {
                break;
            }
            return (const char *)[[NSData dataWithBytes:(attribute + 3) length:strlen(attribute) - 4] bytes];
        }
    }
    return "@";
}

Answer 2

@boliva的答案很好，但是需要一些額外的處理原語，例如int，long，float，double等。

我以他為基礎來添加此功能。

// PropertyUtil.h
#import 

@interface PropertyUtil : NSObject

+ (NSDictionary *)classPropsFor:(Class)klass;

@end


// PropertyUtil.m
#import "PropertyUtil.h"
#import "objc/runtime.h"

@implementation PropertyUtil

static const char * getPropertyType(objc_property_t property) {
    const char *attributes = property_getAttributes(property);
    printf("attributes=%s\n", attributes);
    char buffer[1 + strlen(attributes)];
    strcpy(buffer, attributes);
    char *state = buffer, *attribute;
    while ((attribute = strsep(&state, ",")) != NULL) {
        if (attribute[0] == 'T' && attribute[1] != '@') {
            // it's a C primitive type:
            /* 
                if you want a list of what will be returned for these primitives, search online for
                "objective-c" "Property Attribute Description Examples"
                apple docs list plenty of examples of what you get for int "i", long "l", unsigned "I", struct, etc.            
            */
            return (const char *)[[NSData dataWithBytes:(attribute + 1) length:strlen(attribute) - 1] bytes];
        }        
        else if (attribute[0] == 'T' && attribute[1] == '@' && strlen(attribute) == 2) {
            // it's an ObjC id type:
            return "id";
        }
        else if (attribute[0] == 'T' && attribute[1] == '@') {
            // it's another ObjC object type:
            return (const char *)[[NSData dataWithBytes:(attribute + 3) length:strlen(attribute) - 4] bytes];
        }
    }
    return "";
}


+ (NSDictionary *)classPropsFor:(Class)klass
{    
    if (klass == NULL) {
        return nil;
    }

    NSMutableDictionary *results = [[[NSMutableDictionary alloc] init] autorelease];

    unsigned int outCount, i;
    objc_property_t *properties = class_copyPropertyList(klass, &outCount);
    for (i = 0; i < outCount; i++) {
        objc_property_t property = properties[i];
        const char *propName = property_getName(property);
        if(propName) {
            const char *propType = getPropertyType(property);
            NSString *propertyName = [NSString stringWithUTF8String:propName];
            NSString *propertyType = [NSString stringWithUTF8String:propType];
            [results setObject:propertyType forKey:propertyName];
        }
    }
    free(properties);

    // returning a copy here to make sure the dictionary is immutable
    return [NSDictionary dictionaryWithDictionary:results];
}




@end

Answer 3

@ orange80的答案有一個問題：實際上，它並不總是以0終止字符串。 這可能會導致意外的結果，例如在嘗試將其轉換為UTF8時崩潰（我確實有一個非常煩人的崩潰錯誤，正因為如此。調試它很有趣^^）。 我實際上是通過從屬性獲取NSString，然后調用cStringUsingEncoding：來修復它的。 現在，它就像是一種魅力。 （也與ARC合作，至少對我而言）

所以這是我現在的代碼版本：

// PropertyUtil.h
#import 

@interface PropertyUtil : NSObject

+ (NSDictionary *)classPropsFor:(Class)klass;

@end


// PropertyUtil.m
#import "PropertyUtil.h"
#import <objc/runtime.h>

@implementation PropertyUtil

static const char *getPropertyType(objc_property_t property) {
    const char *attributes = property_getAttributes(property);
    //printf("attributes=%s\n", attributes);
    char buffer[1 + strlen(attributes)];
    strcpy(buffer, attributes);
    char *state = buffer, *attribute;
    while ((attribute = strsep(&state, ",")) != NULL) {
        if (attribute[0] == 'T' && attribute[1] != '@') {
            // it's a C primitive type:
            /*
             if you want a list of what will be returned for these primitives, search online for
             "objective-c" "Property Attribute Description Examples"
             apple docs list plenty of examples of what you get for int "i", long "l", unsigned "I", struct, etc.
             */
            NSString *name = [[NSString alloc] initWithBytes:attribute + 1 length:strlen(attribute) - 1 encoding:NSASCIIStringEncoding];
            return (const char *)[name cStringUsingEncoding:NSASCIIStringEncoding];
        }
        else if (attribute[0] == 'T' && attribute[1] == '@' && strlen(attribute) == 2) {
            // it's an ObjC id type:
            return "id";
        }
        else if (attribute[0] == 'T' && attribute[1] == '@') {
            // it's another ObjC object type:
            NSString *name = [[NSString alloc] initWithBytes:attribute + 3 length:strlen(attribute) - 4 encoding:NSASCIIStringEncoding];
            return (const char *)[name cStringUsingEncoding:NSASCIIStringEncoding];
        }
    }
    return "";
}


+ (NSDictionary *)classPropsFor:(Class)klass
{
    if (klass == NULL) {
        return nil;
    }

    NSMutableDictionary *results = [[NSMutableDictionary alloc] init];

    unsigned int outCount, i;
    objc_property_t *properties = class_copyPropertyList(klass, &outCount);
    for (i = 0; i < outCount; i++) {
        objc_property_t property = properties[i];
        const char *propName = property_getName(property);
        if(propName) {
            const char *propType = getPropertyType(property);
            NSString *propertyName = [NSString stringWithUTF8String:propName];
            NSString *propertyType = [NSString stringWithUTF8String:propType];
            [results setObject:propertyType forKey:propertyName];
        }
    }
    free(properties);

    // returning a copy here to make sure the dictionary is immutable
    return [NSDictionary dictionaryWithDictionary:results];
}

@end

Answer 4

當我嘗試使用iOS 3.2時，getPropertyType函數不能很好地與屬性描述配合使用。 我從iOS文檔中找到了一個示例：“ Objective-C運行時編程指南：聲明的屬性”。

這是iOS 3.2中屬性列表的修訂代碼：

#import <objc/runtime.h>
#import <Foundation/Foundation.h>
...
unsigned int outCount, i;
objc_property_t *properties = class_copyPropertyList([UITouch class], &outCount);
for(i = 0; i < outCount; i++) {
    objc_property_t property = properties[i];
    fprintf(stdout, "%s %s\n", property_getName(property), property_getAttributes(property));
}
free(properties);

Answer 5

我發現boliva的解決方案在模擬器中可以正常工作，但是在設備上固定長度的子字符串會引起問題。 我針對此問題寫了一個更符合Objective-C要求的解決方案，該解決方案可在設備上運行。 在我的版本中，我將屬性的C-String轉換為NSString並對其執行字符串操作以獲得僅具有類型描述的子字符串。

/*
 * @returns A string describing the type of the property
*/

+ (NSString *)propertyTypeStringOfProperty:(objc_property_t) property {
    const char *attr = property_getAttributes(property);
    NSString *const attributes = [NSString stringWithCString:attr encoding:NSUTF8StringEncoding];

    NSRange const typeRangeStart = [attributes rangeOfString:@"T@\""];  // start of type string
    if (typeRangeStart.location != NSNotFound) {
        NSString *const typeStringWithQuote = [attributes substringFromIndex:typeRangeStart.location + typeRangeStart.length];
        NSRange const typeRangeEnd = [typeStringWithQuote rangeOfString:@"\""]; // end of type string
        if (typeRangeEnd.location != NSNotFound) {
            NSString *const typeString = [typeStringWithQuote substringToIndex:typeRangeEnd.location];
            return typeString;
        }
    }
    return nil;
}

/**
* @returns (NSString) Dictionary of property name --> type
*/

+ (NSDictionary *)propertyTypeDictionaryOfClass:(Class)klass {
    NSMutableDictionary *propertyMap = [NSMutableDictionary dictionary];
    unsigned int outCount, i;
    objc_property_t *properties = class_copyPropertyList(klass, &outCount);
    for(i = 0; i < outCount; i++) {
        objc_property_t property = properties[i];
        const char *propName = property_getName(property);
        if(propName) {

            NSString *propertyName = [NSString stringWithCString:propName encoding:NSUTF8StringEncoding];
            NSString *propertyType = [self propertyTypeStringOfProperty:property];
            [propertyMap setValue:propertyType forKey:propertyName];
        }
    }
    free(properties);
    return propertyMap;
}

Answer 6

此實現適用於Objective-C對象類型和C原語。 它與iOS 8兼容。 此類提供了三種方法：

+ (NSDictionary *) propertiesOfObject:(id)object;

返回對象的所有可見屬性的字典，包括其所有超類的屬性。

+ (NSDictionary *) propertiesOfClass:(Class)class;

返回一個類的所有可見屬性的字典，包括其所有超類的屬性。

+ (NSDictionary *) propertiesOfSubclass:(Class)class;

返回特定於子類的所有可見屬性的字典。 不包括其超類的屬性。

使用這些方法的一個有用示例是將對象復制到Objective-C中的子類實例，而不必在copy方法中指定屬性。 該答案的某些部分基於該問題的其他答案，但它為所需功能提供了更簡潔的界面。

標頭：

//  SYNUtilities.h

#import <Foundation/Foundation.h>

@interface SYNUtilities : NSObject
+ (NSDictionary *) propertiesOfObject:(id)object;
+ (NSDictionary *) propertiesOfClass:(Class)class;
+ (NSDictionary *) propertiesOfSubclass:(Class)class;
@end

實現方式：

//  SYNUtilities.m

#import "SYNUtilities.h"
#import <objc/objc-runtime.h>

@implementation SYNUtilities
+ (NSDictionary *) propertiesOfObject:(id)object
{
    Class class = [object class];
    return [self propertiesOfClass:class];
}

+ (NSDictionary *) propertiesOfClass:(Class)class
{
    NSMutableDictionary * properties = [NSMutableDictionary dictionary];
    [self propertiesForHierarchyOfClass:class onDictionary:properties];
    return [NSDictionary dictionaryWithDictionary:properties];
}

+ (NSDictionary *) propertiesOfSubclass:(Class)class
{
    if (class == NULL) {
        return nil;
    }

    NSMutableDictionary *properties = [NSMutableDictionary dictionary];
    return [self propertiesForSubclass:class onDictionary:properties];
}

+ (NSMutableDictionary *)propertiesForHierarchyOfClass:(Class)class onDictionary:(NSMutableDictionary *)properties
{
    if (class == NULL) {
        return nil;
    }

    if (class == [NSObject class]) {
        // On reaching the NSObject base class, return all properties collected.
        return properties;
    }

    // Collect properties from the current class.
    [self propertiesForSubclass:class onDictionary:properties];

    // Collect properties from the superclass.
    return [self propertiesForHierarchyOfClass:[class superclass] onDictionary:properties];
}

+ (NSMutableDictionary *) propertiesForSubclass:(Class)class onDictionary:(NSMutableDictionary *)properties
{
    unsigned int outCount, i;
    objc_property_t *objcProperties = class_copyPropertyList(class, &outCount);
    for (i = 0; i < outCount; i++) {
        objc_property_t property = objcProperties[i];
        const char *propName = property_getName(property);
        if(propName) {
            const char *propType = getPropertyType(property);
            NSString *propertyName = [NSString stringWithUTF8String:propName];
            NSString *propertyType = [NSString stringWithUTF8String:propType];
            [properties setObject:propertyType forKey:propertyName];
        }
    }
    free(objcProperties);

    return properties;
}

static const char *getPropertyType(objc_property_t property) {
    const char *attributes = property_getAttributes(property);
    char buffer[1 + strlen(attributes)];
    strcpy(buffer, attributes);
    char *state = buffer, *attribute;
    while ((attribute = strsep(&state, ",")) != NULL) {
        if (attribute[0] == 'T' && attribute[1] != '@') {
            // A C primitive type:
            /*
             For example, int "i", long "l", unsigned "I", struct.
             Apple docs list plenty of examples of values returned. For a list
             of what will be returned for these primitives, search online for
             "Objective-c" "Property Attribute Description Examples"
             */
            NSString *name = [[NSString alloc] initWithBytes:attribute + 1 length:strlen(attribute) - 1 encoding:NSASCIIStringEncoding];
            return (const char *)[name cStringUsingEncoding:NSASCIIStringEncoding];
        }
        else if (attribute[0] == 'T' && attribute[1] == '@' && strlen(attribute) == 2) {
            // An Objective C id type:
            return "id";
        }
        else if (attribute[0] == 'T' && attribute[1] == '@') {
            // Another Objective C id type:
            NSString *name = [[NSString alloc] initWithBytes:attribute + 3 length:strlen(attribute) - 4 encoding:NSASCIIStringEncoding];
            return (const char *)[name cStringUsingEncoding:NSASCIIStringEncoding];
        }
    }
    return "";
}

@end

Answer 7

如果有人需要很好地獲取從父類繼承的屬性 （如我所做的那樣），則可以對“ orange80 ”代碼進行一些修改以使其遞歸：

+ (NSDictionary *)classPropsForClassHierarchy:(Class)klass onDictionary:(NSMutableDictionary *)results
{
    if (klass == NULL) {
        return nil;
    }

    //stop if we reach the NSObject class as is the base class
    if (klass == [NSObject class]) {
        return [NSDictionary dictionaryWithDictionary:results];
    }
    else{

        unsigned int outCount, i;
        objc_property_t *properties = class_copyPropertyList(klass, &outCount);
        for (i = 0; i < outCount; i++) {
            objc_property_t property = properties[i];
            const char *propName = property_getName(property);
            if(propName) {
                const char *propType = getPropertyType(property);
                NSString *propertyName = [NSString stringWithUTF8String:propName];
                NSString *propertyType = [NSString stringWithUTF8String:propType];
                [results setObject:propertyType forKey:propertyName];
            }
        }
        free(properties);

        //go for the superclass
        return [PropertyUtil classPropsForClassHierarchy:[klass superclass] onDictionary:results];

    }
}

Answer 8

“屬性”一詞有點模糊。 您是說看起來像訪問器的實例變量，屬性，方法嗎？

這三個問題的答案都是“是的，但這不是很容易”。 Objective-C運行時API包括用於獲取類的ivar列表，方法列表或屬性列表的函數（例如， class_copyPropertyList() ），然后包括每種類型的對應函數，以獲取列表中項目的名稱（例如，， property_getName() ）。

總而言之，要想正確使用它可能需要做很多工作，或者至少比大多數人想要做的要多得多，因為通常這只是一個瑣碎的功能。

另外，您可以編寫一個Ruby / Python腳本，該腳本僅讀取頭文件並查找該類的“屬性”。

Answer 9

我能夠得到@ orange80的答案，以便與ARC ENABLED一起工作…………我想要的-至少……但並非沒有嘗試和錯誤。 希望這些附加信息可以使某人免於悲痛。

將他在answer =中描述的那些類保存為類，並在您的AppDelegate.h （或任何其他內容）中，放入#import PropertyUtil.h 。 那你的...

- (void)applicationDidFinishLaunching:
         (NSNotification *)aNotification {

方法（或其他方法） …

PropertyUtil *props  = [PropertyUtil new];  
NSDictionary *propsD = [PropertyUtil classPropsFor:
                          (NSObject*)[gist class]];  
NSLog(@"%@, %@", props, propsD);
…

秘訣是將您要查詢的類的實例變量（ 在本例中，我的類是Gist ，而我的Gist實例是gist ） Gist為 ... 到NSObject … (id)等，不會被剪切..出於各種奇怪而深奧的原因。 這樣將為您提供一些輸出，如…

<PropertyUtil: 0x7ff0ea92fd90>, {
apiURL = NSURL;
createdAt = NSDate;
files = NSArray;
gistDescription = NSString;
gistId = NSString;
gitPullURL = NSURL;
gitPushURL = NSURL;
htmlURL = NSURL;
isFork = c;
isPublic = c;
numberOfComments = Q;
updatedAt = NSDate;
userLogin = NSString;
}

對於蘋果公司一直以來對ObjC的“驚奇”自省的自誇/強迫症患者，他們肯定不會輕易地以這種“眼神”來表現這種簡單的“表情”。

如果您真的想狂野地走..退房.. class-dump ，這是一種令人難以置信的瘋狂方法，可以窺視任何可執行文件的類頭，等等。。。它為您的類提供了VERBOSE外觀……我，就個人而言，在很多情況下都可以找到真正有用的方法。 實際上，這就是為什么我開始尋求OP的問題的解決方案的原因。 這里是一些使用參數..享受！

    -a             show instance variable offsets
    -A             show implementation addresses
    --arch <arch>  choose a specific architecture from a universal binary (ppc, ppc64, i386, x86_64)
    -C <regex>     only display classes matching regular expression
    -f <str>       find string in method name
    -I             sort classes, categories, and protocols by inheritance (overrides -s)
    -r             recursively expand frameworks and fixed VM shared libraries
    -s             sort classes and categories by name
    -S             sort methods by name

Answer 10

我使用的是提供的功能boliva，但顯然它已停止與iOS 7一起使用。因此，現在可以使用以下方法代替靜態const char * getPropertyType（objc_property_t屬性）：

- (NSString*) classOfProperty:(NSString*)propName{

objc_property_t prop = class_getProperty([self class], [propName UTF8String]);
if (!prop) {
    // doesn't exist for object
    return nil;
}
const char * propAttr = property_getAttributes(prop);
NSString *propString = [NSString stringWithUTF8String:propAttr];
NSArray *attrArray = [propString componentsSeparatedByString:@","];
NSString *class=[attrArray objectAtIndex:0];
return [[class stringByReplacingOccurrencesOfString:@"\"" withString:@""] stringByReplacingOccurrencesOfString:@"T@" withString:@""];
}

Answer 11

你有三個魔法

Ivar* ivars = class_copyIvarList(clazz, &count); // to get all iVars
objc_property_t  *properties = class_copyPropertyList(clazz, &count); //to get all properties of a class 
Method* methods = class_copyMethodList(clazz, &count); // to get all methods of a class.

以下代碼段可以為您提供幫助。

-(void) displayClassInfo
{
    Class clazz = [self class];
    u_int count;

    Ivar* ivars = class_copyIvarList(clazz, &count);
    NSMutableArray* ivarArray = [NSMutableArray arrayWithCapacity:count];
    for (int i = 0; i < count ; i++)
    {
        const char* ivarName = ivar_getName(ivars[i]);
        ivarArray addObject:[NSString  stringWithCString:ivarName encoding:NSUTF8StringEncoding]];
    }
    free(ivars);

    objc_property_t* properties = class_copyPropertyList(clazz, &count);
    NSMutableArray* propertyArray = [NSMutableArray arrayWithCapacity:count];
    for (int i = 0; i < count ; i++)
    {
        const char* propertyName = property_getName(properties[i]);
        [propertyArray addObject:[NSString  stringWithCString:propertyName encoding:NSUTF8StringEncoding]];
    }
    free(properties);

    Method* methods = class_copyMethodList(clazz, &count);
    NSMutableArray* methodArray = [NSMutableArray arrayWithCapacity:count];
    for (int i = 0; i < count ; i++)
    {
        SEL selector = method_getName(methods[i]);
        const char* methodName = sel_getName(selector);
        [methodArray addObject:[NSString  stringWithCString:methodName encoding:NSUTF8StringEncoding]];
    }
    free(methods);

    NSDictionary* classInfo = [NSDictionary dictionaryWithObjectsAndKeys:
                           ivarArray, @"ivars",
                           propertyArray, @"properties",
                           methodArray, @"methods",
                           nil];

        NSLog(@"%@", classInfo);
}

Answer 12

這些答案很有幫助，但是我需要更多的答案。 我要做的就是檢查屬性的類類型是否等於現有對象的類類型。 上面的所有代碼均無法執行此操作，因為：為了獲取對象的類名，object_getClassName（）返回如下文本：

__NSArrayI (for an NSArray instance)
__NSArrayM (for an NSMutableArray instance)
__NSCFBoolean (an NSNumber object initialized by initWithBool:)
__NSCFNumber (an NSValue object initialized by [NSNumber initWithBool:])

但是，如果從上述示例代碼中調用getPropertyType（...），則將這樣定義的類的屬性的4個objc_property_t結構構造為：

@property (nonatomic, strong) NSArray* a0;
@property (nonatomic, strong) NSArray* a1;
@property (nonatomic, copy) NSNumber* n0;
@property (nonatomic, copy) NSValue* n1;

它分別返回字符串，如下所示：

NSArray
NSArray
NSNumber
NSValue

因此，無法確定NSObject是否能夠作為該類的一個屬性的值。 那怎么辦呢？

這是我的完整示例代碼（函數getPropertyType（...）與上面相同）：

#import <objc/runtime.h>

@interface FOO : NSObject

@property (nonatomic, strong) NSArray* a0;
@property (nonatomic, strong) NSArray* a1;
@property (nonatomic, copy) NSNumber* n0;
@property (nonatomic, copy) NSValue* n1;

@end

@implementation FOO

@synthesize a0;
@synthesize a1;
@synthesize n0;
@synthesize n1;

@end

static const char *getPropertyType(objc_property_t property) {
    const char *attributes = property_getAttributes(property);
    //printf("attributes=%s\n", attributes);
    char buffer[1 + strlen(attributes)];
    strcpy(buffer, attributes);
    char *state = buffer, *attribute;
    while ((attribute = strsep(&state, ",")) != NULL) {
        if (attribute[0] == 'T' && attribute[1] != '@') {
            // it's a C primitive type:

            // if you want a list of what will be returned for these primitives, search online for
            // "objective-c" "Property Attribute Description Examples"
            // apple docs list plenty of examples of what you get for int "i", long "l", unsigned "I", struct, etc.

            NSString *name = [[NSString alloc] initWithBytes:attribute + 1 length:strlen(attribute) - 1 encoding:NSASCIIStringEncoding];
            return (const char *)[name cStringUsingEncoding:NSASCIIStringEncoding];
        }
        else if (attribute[0] == 'T' && attribute[1] == '@' && strlen(attribute) == 2) {
            // it's an ObjC id type:
            return "id";
        }
        else if (attribute[0] == 'T' && attribute[1] == '@') {
            // it's another ObjC object type:
            NSString *name = [[NSString alloc] initWithBytes:attribute + 3 length:strlen(attribute) - 4 encoding:NSASCIIStringEncoding];
            return (const char *)[name cStringUsingEncoding:NSASCIIStringEncoding];
        }
    }
    return "";
}

int main(int argc, char * argv[]) {
    NSArray* a0 = [[NSArray alloc] init];
    NSMutableArray* a1 = [[NSMutableArray alloc] init];
    NSNumber* n0 = [[NSNumber alloc] initWithBool:YES];
    NSValue* n1 = [[NSNumber alloc] initWithBool:NO];
    const char* type0 = object_getClassName(a0);
    const char* type1 = object_getClassName(a1);
    const char* type2 = object_getClassName(n0);
    const char* type3 = object_getClassName(n1);

    objc_property_t property0 = class_getProperty(FOO.class, "a0");
    objc_property_t property1 = class_getProperty(FOO.class, "a1");
    objc_property_t property2 = class_getProperty(FOO.class, "n0");
    objc_property_t property3 = class_getProperty(FOO.class, "n1");
    const char * memberthype0 = getPropertyType(property0);//property_getAttributes(property0);
    const char * memberthype1 = getPropertyType(property1);//property_getAttributes(property1);
    const char * memberthype2 = getPropertyType(property2);//property_getAttributes(property0);
    const char * memberthype3 = getPropertyType(property3);//property_getAttributes(property1);
    NSLog(@"%s", type0);
    NSLog(@"%s", type1);
    NSLog(@"%s", type2);
    NSLog(@"%s", type3);
    NSLog(@"%s", memberthype0);
    NSLog(@"%s", memberthype1);
    NSLog(@"%s", memberthype2);
    NSLog(@"%s", memberthype3);

    return 0;
}

Answer 13

對於Swift圍觀者，您可以通過使用Encodable功能來獲得此功能。 我將解釋如何：

使您的對象符合可Encodable協議

 class ExampleObj: NSObject, Encodable { var prop1: String = "" var prop2: String = "" }

為Encodable創建擴展以提供toDictionary功能

  public func toDictionary() -> [String: AnyObject]? { let encoder = JSONEncoder() encoder.outputFormatting = .prettyPrinted guard let data = try? encoder.encode(self), let json = try? JSONSerialization.jsonObject(with: data, options: .init(rawValue: 0)), let jsonDict = json as? [String: AnyObject] else { return nil } return jsonDict }

在對象實例和訪問keys屬性上調用toDictionary 。

 let exampleObj = ExampleObj() exampleObj.toDictionary()?.keys

瞧！ 像這樣訪問您的屬性：

 for k in exampleObj!.keys { print(k) } // Prints "prop1" // Prints "prop2"

在Objective-C中獲取對象屬性列表

問題描述

13 個解決方案

解決方案1
116 已采納 2009-04-16 07:45:49

解決方案2
74 2011-12-05 03:55:38

解決方案3
28 2012-10-21 17:03:50

解決方案4
8 2010-10-24 13:08:29

解決方案5
7 2012-08-09 09:13:29

解決方案6
6 2014-12-06 21:03:23

解決方案7
4 2013-08-19 12:21:30

解決方案8
3 2009-04-16 05:40:14

解決方案9
3 2012-03-31 06:51:23

解決方案10
2 2013-08-17 18:14:37

解決方案11
2 2015-06-25 12:21:57

解決方案12
1 2015-03-25 07:09:39

解決方案13
1 2018-05-21 14:00:10

在Objective-C中獲取對象屬性列表

問題描述

13 個解決方案

解決方案1 116 已采納 2009-04-16 07:45:49

解決方案2 74 2011-12-05 03:55:38

解決方案3 28 2012-10-21 17:03:50

解決方案4 8 2010-10-24 13:08:29

解決方案5 7 2012-08-09 09:13:29

解決方案6 6 2014-12-06 21:03:23

解決方案7 4 2013-08-19 12:21:30

解決方案8 3 2009-04-16 05:40:14

解決方案9 3 2012-03-31 06:51:23

解決方案10 2 2013-08-17 18:14:37

解決方案11 2 2015-06-25 12:21:57

解決方案12 1 2015-03-25 07:09:39

解決方案13 1 2018-05-21 14:00:10

解決方案1
116 已采納 2009-04-16 07:45:49

解決方案2
74 2011-12-05 03:55:38

解決方案3
28 2012-10-21 17:03:50

解決方案4
8 2010-10-24 13:08:29

解決方案5
7 2012-08-09 09:13:29

解決方案6
6 2014-12-06 21:03:23

解決方案7
4 2013-08-19 12:21:30

解決方案8
3 2009-04-16 05:40:14

解決方案9
3 2012-03-31 06:51:23

解決方案10
2 2013-08-17 18:14:37

解決方案11
2 2015-06-25 12:21:57

解決方案12
1 2015-03-25 07:09:39

解決方案13
1 2018-05-21 14:00:10