NSPrintInfo localizedPaperName，如何在ios中获取纸张名称？

Question

在我的mac上，我使用NSPrintInfo和NSPrintInfo localizedPaperName来确定默认的纸张大小是“美国字母”还是"A4“。

NSPrintInfo * printInfo = NSPrintInfo sharedPrintInfo；printInfo localizedPaperName

如何让iOS设备告诉我，默认的纸张大小是“美国字母”还是"A4"？

Answer 1

由于没有人提出更好的方法，我查了一下使用美国字母的国家，然后开始根据这个列表检查，得到了NSLocaleCountryCode

 [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"US"]||
        [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"CA"]||
        [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"MX"]||
        [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"CU"]||
        [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"DO"]||
        [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"GT"]||
        [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"CR"]||
        [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"SV"]||
        [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"HN"]||
        [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"BO"]||
        [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"CO"]||
        [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"VE"]||
        [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"PH"]||
        [[[NSLocale currentLocale] objectForKey:NSLocaleCountryCode] isEqualToString:@"CL"]

Answer 2

我使用了类似@spacecash21 21建议的类似的固定列表方法，基于这张地图：size.svg

+ (NSString*)defaultPaperName
{
    // as it looks mostly US and Canada and the Philippines are actually using the US Letter format, usage of the metric system is no clue
    // https://en.wikipedia.org/wiki/Paper_size#/media/File:Prevalent_default_paper_size.svg
    static NSSet* letterCountries;
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        letterCountries = [NSSet setWithArray:@[@"US", @"CA", @"MX", @"CU", @"DO", @"GT", @"CR", @"SV", @"HN", @"BO", @"CO", @"VE", @"PH", @"CL"]];
    });

    NSString* countryCode = NSLocale.currentLocale.countryCode;
    if ([letterCountries containsObject:countryCode.uppercaseString])
        return @"na-letter";

    return @"iso-a4";
}