NSNumberFormatter 应该可以满足你对数据形式的一般需求,值得了解一下

    NSNumber *num1 = [NSNumber numberWithDouble:1234567.8369];    // ==================== 类方法 ====================    // 四舍五入的整数    NSString *numberNoStyleStr                 = [NSNumberFormatter localizedStringFromNumber:num1 numberStyle:NSNumberFormatterNoStyle];    // 小数形式    NSString *numberDecimalStyleStr            = [NSNumberFormatter localizedStringFromNumber:num1 numberStyle:NSNumberFormatterDecimalStyle];    // 货币形式 -- 本地化    NSString *numberCurrencyStyleStr           = [NSNumberFormatter localizedStringFromNumber:num1 numberStyle:NSNumberFormatterCurrencyStyle];    // 百分数形式    NSString *numberPercentStyleStr            = [NSNumberFormatter localizedStringFromNumber:num1 numberStyle:NSNumberFormatterPercentStyle];    // 科学计数    NSString *numberScientificStyleStr         = [NSNumberFormatter localizedStringFromNumber:num1 numberStyle:NSNumberFormatterScientificStyle];    // 朗读形式 -- 本地化    NSString *numberSpellOutStyleStr           = [NSNumberFormatter localizedStringFromNumber:num1 numberStyle:NSNumberFormatterSpellOutStyle];    // 序数形式 -- 本地化    NSString *numberOrdinalStyleStr            = [NSNumberFormatter localizedStringFromNumber:num1 numberStyle:NSNumberFormatterOrdinalStyle];    // 货币形式 ISO -- 本地化    NSString *numberCurrencyISOStyleStr        = [NSNumberFormatter localizedStringFromNumber:num1 numberStyle:NSNumberFormatterCurrencyISOCodeStyle];    // 货币形式 -- 本地化    NSString *numberCurrencyPluralStyleStr     = [NSNumberFormatter localizedStringFromNumber:num1 numberStyle:NSNumberFormatterCurrencyPluralStyle];    // 会计计数 -- 本地化    NSString *numberCurrencyAccountingStyleStr = [NSNumberFormatter localizedStringFromNumber:num1 numberStyle:NSNumberFormatterCurrencyAccountingStyle];    NSLog(@"No Style                  = %@",numberNoStyleStr);                // No Style                  = 1234568    NSLog(@"Decimal Style             = %@",numberDecimalStyleStr);           // Decimal Style             = 1,234,567.837    NSLog(@"Currency Style            = %@",numberCurrencyStyleStr);          // Currency Style            = $1,234,567.84    NSLog(@"Percent Style             = %@",numberPercentStyleStr);           // Percent Style             = 123,456,784%    NSLog(@"Scientific Style          = %@",numberScientificStyleStr);        // Scientific Style          = 1.2345678369E6    // Spell Out Style           = one million two hundred thirty-four thousand five hundred sixty-seven point eight three six nine    NSLog(@"Spell Out Style           = %@",numberSpellOutStyleStr);    NSLog(@"Ordinal Style             = %@",numberOrdinalStyleStr);            // Ordinal Style             = 1,234,568th    NSLog(@"Currency ISO Style        = %@",numberCurrencyISOStyleStr);        // Currency ISO Style        = USD1,234,567.84    NSLog(@"Currency plural Style     = %@",numberCurrencyPluralStyleStr);     // Currency plural Style     = 1,234,567.84 US dollars    NSLog(@"Currency accounting Style = %@",numberCurrencyAccountingStyleStr); // Currency accounting Style = $1,234,567.84    // ==================== 定制 ====================    NSNumberFormatter *numberFormatter = [NSNumberFormatter new];    numberFormatter.numberStyle = NSNumberFormatterDecimalStyle;    // 格式宽度    numberFormatter.formatWidth = 15;    // 填充符    numberFormatter.paddingCharacter = @"?";    // 填充位置    numberFormatter.paddingPosition = kCFNumberFormatterPadBeforeSuffix;    numberFormatter.positiveSuffix = @"元";    NSLog(@"%@",[numberFormatter numberFromString:@"10000000元"]);  // 10000000    // 缩放因子,你可以将一个数缩放指定比例,然后给其添加后缀,如传入一个3000,你希望表示为3千,就要用到这个属性    // 防止影响后面的测试,故注掉//    numberFormatter.multiplier = @1000;//    NSLog(@"%@千",[numberFormatter numberFromString:@"1000"]);  // 1千//    numberFormatter.multiplier     = @0.001;//    numberFormatter.positiveSuffix = @"千";//    NSLog(@"%@",[numberFormatter stringFromNumber:@10000]);    // 10千    // 机制不明确,负号,正号//    numberFormatter.negativeFormat = @"^";//    numberFormatter.positiveFormat = @"~0";    // 貌似没什么用    numberFormatter.allowsFloats = NO;    numberFormatter.alwaysShowsDecimalSeparator = NO;    numberFormatter.maximum = @1000;    numberFormatter.minimum = @100;    // 小数点样式    numberFormatter.decimalSeparator = @".";    // 零的样式    numberFormatter.zeroSymbol       = @"-";    // 前缀和后缀    numberFormatter.positivePrefix = @"!";    numberFormatter.positiveSuffix = @"元";    numberFormatter.negativePrefix = @"@";    numberFormatter.negativeSuffix = @"亏";    // 指定符号,与我们在前面类方法中说明的一致    NSLog(@"货币代码%@",numberFormatter.currencyCode);                     // 货币代码USD    NSLog(@"货币符号%@",numberFormatter.currencySymbol);                   // 货币符号$    NSLog(@"国际货币符号%@",numberFormatter.internationalCurrencySymbol);   // 国际货币符号USD    NSLog(@"百分比符号%@",numberFormatter.percentSymbol);                   // 百分比符号%    NSLog(@"千分号符号%@",numberFormatter.perMillSymbol);                   // 千分号符号‰    NSLog(@"减号符号%@",numberFormatter.minusSign);                         // 减号符号-    NSLog(@"加号符号%@",numberFormatter.plusSign);                          // 加号符号+    NSLog(@"指数符号%@",numberFormatter.exponentSymbol);                    // 指数符号E    // 整数最多位数    numberFormatter.maximumIntegerDigits = 10;    // 整数最少位数    numberFormatter.minimumIntegerDigits = 2;    // 小数位最多位数    numberFormatter.maximumFractionDigits = 3;    // 小数位最少位数    numberFormatter.minimumFractionDigits = 1;    // 数字分割的尺寸    numberFormatter.groupingSize = 4;    // 除了groupingSize决定的尺寸外,其他数字位分割的尺寸    numberFormatter.secondaryGroupingSize = 2;    // 最大有效数字个数    numberFormatter.maximumSignificantDigits = 12;    // 最少有效数字个数    numberFormatter.minimumSignificantDigits = 3;    NSLog(@"正数%@,负数%@",[numberFormatter stringFromNumber:@(+12135230.2346)],[numberFormatter stringFromNumber:@(-12135231.2346)]);  // 正数!12,13,5230.2346元,负数@12,13,5231.2346亏    NSLog(@"零 = %@",[numberFormatter stringFromNumber:@(0)]); //  零 = -    // 舍入值,比如以10为进位值,那么156就进位为160,154进位为150    numberFormatter.roundingIncrement = @10;    // 舍入方式    numberFormatter.roundingMode = kCFNumberFormatterRoundHalfUp;    NSLog(@"%@",[numberFormatter stringFromNumber:@123456.7890]);  // !12,3460元