float INFINITY可以由NSCoder存档，但不能取消存档 [英] float INFINITY can be archived by NSCoder, but not dearchived

问题描述

我必须将值INFINITY的float存档，然后对其进行解存档.
这是我的示例代码:

I have to archive a float with value INFINITY, and later to dearchive it.
Here is my example code:

要归档的对象:

@interface CodeInf : NSObject <NSCoding>
@end
@implementation CodeInf
- (void)encodeWithCoder:(NSCoder *)encoder {
    float inf = INFINITY;
    [encoder encodeFloat: inf forKey:@"INFINITY"];
}
- (id)initWithCoder:(NSCoder *)decoder {
    if (self = [super init]) {
        float decodedInf = [decoder decodeFloatForKey: @"INFINITY"];
    }
    return self;
}
@end

这是归档/归档代码:

CodeInf *myCodeInf = [[CodeInf alloc] init];
NSData *data = [NSKeyedArchiver archivedDataWithRootObject:myCodeInf];
myCodeInf = [NSKeyedUnarchiver unarchiveObjectWithData:data];

归档可以工作，但是归档会引发错误:

Archiving works, but dearchiving raises the error:

*由于未捕获的异常'NSRangeException'而终止应用程序，原因:'* -[NSKeyedUnarchiver encodeFloatForKey:]:的值(inf)为 键(INFINITY)太大，无法放入32位浮点数"

* Terminating app due to uncaught exception 'NSRangeException', reason: '* -[NSKeyedUnarchiver decodeFloatForKey:]: value (inf) for key (INFINITY) too large to fit in 32-bit float'

这是解压缩程序中的错误，还是我出了什么问题?

Is this a bug in the dearchiver, or do I something wrong?

推荐答案

看起来像个错误.向苹果提交错误报告.

Looks like a bug. Submit a bug report to Apple.

作为解决方法，请使用encodeDouble和decodeDoubleForKey-您可以将值保留为float，并且C规则不需要强制转换.

As a workaround use encodeDouble and decodeDoubleForKey - you can keep your value as a float and no casts are needed by C rules.

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