1、NSNumber转NSString

                NSNumber *number = @(YES);if(number && [number isKindOfClass:[NSNumber class]]){//若考虑为空或NSString类型的情况，该方法兼容性比较好NSString *String = [NSString StringWithFormat:@"%@",number];//或者 该方法一定要判断类型不然可能闪退
//                    NSString *String = number.description;}

NSString字符串如何转为NSNumber

2、NSString 转 NSNumber

                NSString *str = @"327691";NSNumber *number = nil;if(str){number = @(0);}else if([str isKindOfClass:[NSString class]]){// 字符串先转成long long类型，再转对象number = @([str longLongValue]);}