如何将格式化的 nsstring 转换为 NSNumber 或删除格式？答案

【问题标题】：How convert a formated nsstring to NSNumber or just remove the format?如何将格式化的 nsstring 转换为 NSNumber 或删除格式？
【发布时间】：2012-09-26 10:28:19
【问题描述】：

我有一个类似“1.23,45”的字符串，（德国/法国风格或其他风格）。如何将格式删除为普通字符串或 nsnumber？我只知道从数字转换为字符串。:( 谢谢。

【问题讨论】：

标签： iphone ios xcode ipad

【解决方案1】：

NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init];  
    [formatter setNumberStyle:NSNumberFormatterCurrencyStyle];
    [formatter setCurrencySymbol:@""];  

    NSLocale *locale = [[NSLocale alloc] initWithLocaleIdentifier:@"en_US"];
    [formatter setLocale:locale];
    NSString *formattedOutput = [formatter stringFromNumber:[NSNumber numberWithFloat:[aPrice floatValue]]];
    [locale release];
    [formatter release];
    NSLog(@"%@", formattedOutput];

进一步将formattedString转换为数字

NSNumber myNumber = [formattedOutput intValue]; //replace intValue by floatValue to get decimal output

【讨论】：

【解决方案2】：

您可以使用NSNumberFormatter 将NSString 转换为NSNumber，但您必须告诉它您为字符串使用的语言环境（在这种情况下为德语）：

// Create a number formatter that can convert from/to German currency:
NSNumberFormatter *formatter    = [[NSNumberFormatter alloc] init];
formatter.numberStyle           = NSNumberFormatterCurrencyStyle;
formatter.locale                = [[NSLocale alloc] initWithLocaleIdentifier:@"de_DE"];
[formatter setLenient:YES];

// Use the number formatter to create a NSNumber:
NSNumber *number                = [formatter numberFromString:@"1.23,45"];

// Return the number formatter to the current user's locale:
formatter.locale                = [NSLocale currentLocale];

// Finally, create a string from the NSNumber formatted in the user's locale:
NSString *formattedString       = [formatter stringFromNumber:number];

【讨论】：

【解决方案3】：

  NSNumber * myNumber  = [NSNumber numberWithInt:[@"1.23,45" intValue]];

或

  NSNumber * myNumber  = [NSNumber numberWithFloat:[@"1.23,45" floatValue]];

注意：最好去掉字符串中的逗号（,）符号

您可以使用以下方法

+ (NSNumber *)numberWithChar:(char)value;
+ (NSNumber *)numberWithUnsignedChar:(unsigned char)value;
+ (NSNumber *)numberWithShort:(short)value;
+ (NSNumber *)numberWithUnsignedShort:(unsigned short)value;
+ (NSNumber *)numberWithInt:(int)value;
+ (NSNumber *)numberWithUnsignedInt:(unsigned int)value;
+ (NSNumber *)numberWithLong:(long)value;
+ (NSNumber *)numberWithUnsignedLong:(unsigned long)value;
+ (NSNumber *)numberWithLongLong:(long long)value;
+ (NSNumber *)numberWithUnsignedLongLong:(unsigned long long)value;
+ (NSNumber *)numberWithFloat:(float)value;
+ (NSNumber *)numberWithDouble:(double)value;
+ (NSNumber *)numberWithBool:(BOOL)value;
+ (NSNumber *)numberWithInteger:(NSInteger)value NS_AVAILABLE(10_5, 2_0);
+ (NSNumber *)numberWithUnsignedInteger:(NSUInteger)value NS_AVAILABLE(10_5, 2_0);

【讨论】：

嗨 Ramshad，我试过这个，但它不起作用，它返回 nil。我认为它不知道逗号

【解决方案4】：

听起来你需要做两件事：

1) 根据逗号分隔将字符串分解为子字符串数组

NSString *startString = @"1.23,45";
NSArray *subStringArray= [colorStr componentsSeparatedByString:@","];

2) 将每个子字符串转换为数字

NSNumberFormatter * formatter = [[NSNumberFormatter alloc] init];
[formatter setNumberStyle:NSNumberFormatterDecimalStyle];
NSString *subString = [subStringArray objectAtIndex:0];
NSNumber *thisNumber = [formatter numberFromString:subString];
NSLog (@"thisNumber: %@", thisNumber);

【讨论】：