3
我是Objective-c的新手。我正在写一个简单的方法来字典转换为对象来练习KVC知识:Objective-C KVC更改属性的类型
+(id) ConvertDictionary:(NSDictionary *)dict
ToClassInstance:(Class)type{
id targetObj = nil;
if(dict){
NSArray *dictKeys = dict.allKeys;
targetObj = [[type alloc] init];
for (NSString*item in dictKeys) {
[targetObj setValue:[dict objectForKey:item] forKey:item];
}
}
}
return targetObj;
}
和一个简单的类:
#import <Foundation/Foundation.h>
@interface foo : NSObject
@property (nonatomic) int value;
@property(nonatomic,strong) NSDate *dateTime;
@end
并运行下面的代码的方法:
-(void)testConvert
{
NSArray *value = [NSArray arrayWithObjects:
[NSNumber numberWithInt:2],@"wrongDateString",nil];
NSArray *key = [NSArray arrayWithObjects:@"value",@"dateTime", nil];
NSDictionary *dict = [NSDictionary dictionaryWithObjects: value forKeys:key];
id result= [EPMClassUtility ConvertDictionary:dict
ToClassInstance:[foo class]];
foo *convert = (foo*) result;
NSLog(@"get value: %@",convert.dateTime);
//console write the line: get value:wrongDateString
}
我的问题是,我通过setValue:forKey:给出了一个错误类型的值(应该是NSDate,但实际上是NSString)。但为什么运行时或XCode中不会发生异常,以及属性dateTime如何接受NSString值?
在运行时中(几乎)没有类型检查objc – 2013-03-27 09:23:41