ios将银行卡号格式化

by 伍雪颖

- (NSString *)formatCardNumber:(NSString *)cardNum {    NSNumber *number = @([cardNum longLongValue]);    NSNumberFormatter *formatter = [NSNumberFormatter new];    [formatter setUsesGroupingSeparator:YES];    [formatter setGroupingSize:4];    [formatter setGroupingSeparator:@" "];    return [formatter stringFromNumber:number];}