1   2  3 //使用此方法转换即可 4  5   6  7 - (NSString *)formartScientificNotationWithString:(NSString *)str{ 8  9     long double num = [[NSString stringWithFormat:@"%@",str] floatValue];10 11     NSNumberFormatter * formatter = [[NSNumberFormatter alloc]init];12 13     formatter.numberStyle = kCFNumberFormatterNoStyle;14 15     NSString * string = [formatter stringFromNumber:[NSNumber numberWithDouble:num]];16 17     return [NSString calculateFormat:string];18 19 }20 21