## Objective-C KVC 自己主动转换类型研究

apple非常厚道,kvc的时候帮我们做了一些类型转换,规律贴出来,给大伙參考參考

@interface Entity : NSObject

@property (nonatomic, copy) NSString *str;

@property (nonatomic, assign) int i1;

@property (nonatomic, assign) int i2;

@property (nonatomic, assign) int i3;

@property (nonatomic, assign) float f1;

@property (nonatomic, strong) NSNumber *num;

@property (nonatomic, assign) BOOL b1;

@property (nonatomic, assign) BOOL b2;

@property (nonatomic, assign) BOOL b3;

@property (nonatomic, strong) NSDate *date1;

@property (nonatomic, assign) NSTimeInterval t1;

@end

	// 数值的字串能够转成数值类型

    [obj setValue:@"2.4" forKey:@"i1"];

    // 非数值的字串不认识

    [obj setValue:@"a" forKey:@"i2"];

    // 仅仅认识特殊符号曾经的数

    [obj setValue:@"2014 10-24" forKey:@"i3"];

    // 这个转换过去是NSNumber类型

    [obj setValue:@1 forKey:@"str"];

    [obj setValue:@1.23 forKey:@"f1"];

    // 转去还是NSString

    [obj setValue:@"99" forKey:@"num"];

    // >= 1.0 为真, 1.0下面为假

    [obj setValue:@0.9 forKey:@"b1"];

    // >= 1.0 为真, 1.0下面为假

    [obj setValue:@"1.1" forKey:@"b2"];

    // true TRUE yes YES false FALSE no NO 都能够识别

    [obj setValue:@"TRUE" forKey:@"b3"];

    // 转去还是NSTring

    [obj setValue:@"2014-10-24" forKey:@"date1"];

    // 不认识

    [obj setValue:@"2014-10-24" forKey:@"t1"];

    // 结论

    // 数值类型的字串 to 数值 能够转行成数值

    // 类 to 类 不转换直接赋值