model转字典

+ (NSDictionary *) entityToDictionary:(id)entity  

{  

    Class clazz = [entity class];  

    u_int count;  

    objc_property_t* properties = class_copyPropertyList(clazz, &count);  

    NSMutableArray* propertyArray = [NSMutableArray arrayWithCapacity:count];  

    NSMutableArray* valueArray = [NSMutableArray arrayWithCapacity:count];  

    for (int i = 0; i < count ; i++)  

    {  

        objc_property_t prop=properties[i];  

        const char* propertyName = property_getName(prop);  

        [propertyArray addObject:[NSString stringWithCString:propertyName encoding:NSUTF8StringEncoding]];  

        //        const char* attributeName = property_getAttributes(prop);  

        //        NSLog(@"%@",[NSString stringWithUTF8String:propertyName]);  

        //        NSLog(@"%@",[NSString stringWithUTF8String:attributeName]);  

        id value =  [entity performSelector:NSSelectorFromString([NSString stringWithUTF8String:propertyName])];  

        if(value ==nil)  

            [valueArray addObject:[NSNull null]];  

        else {  

            [valueArray addObject:value];  

        }  

        //        NSLog(@"%@",value);  

    }  

    free(properties);  

    NSDictionary* returnDic = [NSDictionary dictionaryWithObjects:valueArray forKeys:propertyArray];  

    NSLog(@"%@", returnDic);  

    return returnDic;  

}