如何在Objective-C中解析对象以获得键值(属性/值)? [英] How to parse an object to obtain keys values (attribute/value) in Objective-C?

问题描述

我想获取Objective-C中对象的所有属性的值.
例如，我有一个名为Client1的类Client的实例.
我想有一个方法来获取该对象作为参数并返回属性和值. (name = 'nameC1'，age = 21，...)

I want to get the values of all attributes of an object in Objective-C.
For example I have an instance of my class Client, named Client1.
I would like to have a method which get this object as a parameter and returns the attributes and values. (name = 'nameC1', age = 21, ...)

推荐答案

这个问题有些不同，但是我认为答案与您的问题的答案相同

This question was a bit different, but I think the answer is the same as the answer to your question:

https://stackoverflow.com/a/8380836/104527

// 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

要使用导入PropertyUtil.h并执行以下操作:

To use import PropertyUtil.h and do something like:

NSDictionary props = [PropertyUtil classPropsFor:[YourClass class]];

这篇关于如何在Objective-C中解析对象以获得键值(属性/值)?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！