ios 自定义对象转json

我想说：切换成markdown模式的时候保存按钮被挡住了。。导致半天也没闹明白为啥没生效！！！

+(NSDictionary *)getObjectData:(id)obj {   
    NSMutableDictionary *dic = [NSMutableDictionary dictionary];
    unsigned int propsCount;
    objc_property_t *props = class_copyPropertyList([obj class], &propsCount);
    for(int i = 0;i < propsCount; i++){
        objc_property_t prop = props[i];
        
        NSString *propName = [NSString stringWithUTF8String:property_getName(prop)];
        id value = [obj valueForKey:propName];
        if(value == nil){
            value = [NSNull null];
        }else{
            value = [self getObjectInternal:value];
        }
        [dic setObject:value forKey:propName];
    }
    return dic; 
} 

苍天啊！！这个代码框终于出来了！！