Question

这是我的函数，通过输入值，输入的基数，转换的基数将基数转换为基数

代码：

Create Function dbo.Unit_Base_To_Base(@Input as nvarchar(60),@Base as int, @NewBase as int)
Returns nvarchar(450)
as begin
Declare @Chartable table(Value  int,Char nvarchar(100)) 
Declare @list Table(val bigint) 
DECLARE @I bigint = 1, 
@Formula bigint, 
@I2 bigint=1, 
@Formula2 varchar(100)
Declare @Ilength bigint = (cast(len(@Input) as nvarchar(60)))
Declare @I2length2 bigint
--------------Value Table
Insert into @Chartable(Value,char)
Values(0,'0')
, (1,'1')
, (2,'2')
, (3,'3')
, (4,'4')
, (5,'5')
, (6,'6')
, (7,'7')
, (8,'8')
, (9,'9')
, (10,'A')
, (11,'B')
, (12,'C')
, (13,'D')
, (14,'E')
, (15,'F')
, (16,'G')
, (17,'H')
, (18,'I')
, (19,'J')
, (20,'K')
, (21,'L')
, (22,'M')
, (23,'N')
, (24,'O')
, (25,'P')
, (26,'Q')
, (27,'R')
, (28,'S')
, (29,'T')
, (30,'U')
, (31,'V')
, (32,'W')
, (33,'X')
, (34,'Y')
, (35,'Z')

------------Convertion Start to 10


SET @Formula = ((Power(convert(bigint,@Base) , (@Ilength-1)))*(Cast( (select Value from @Chartable where char=(SUBSTRING(@input,1,1))) as bigint)))
WHILE @I <= (cast(@Ilength as bigint))
BEGIN
insert into @list(val)
values(@Formula)
    SET @I = @I + 1
     SET @Formula =  (cast((Power(convert(bigint,@Base) , (@Ilength-@I)))*(Cast( (select value from @Chartable where char =(SUBSTRING(@input,@I,1))) as bigint))as bigint))
END

------------Convertion Start to base
Declare @I2nput2 as nvarchar(60) = (select sum(val) from @list)
If @newbase<10 begin set @I2length2 = LOG(@I2nput2,@newbase)+1 end else begin  set @I2length2 = (cast(len(@I2nput2) as bigint)) end
SET @Formula2 = (select char from @Chartable where value=(cast(((CAST(@I2nput2 as bigint))-(((CAST(@I2nput2 as bigint))/(Power(convert(bigint,@newbase) , (@I2length2+1)))))*(Power(convert(bigint,@newbase) , (@I2length2))))/(Power(convert(bigint,@newbase) , (@I2length2-1))) as nvarchar(450))))
WHILE @I2 <= (cast(@I2length2 as bigint))
BEGIN

    SET @I2 = @I2 + 1
     SET @Formula2 =  @Formula2 + (select char from @Chartable where value=(cast(Cast(Isnull(((CAST(@I2nput2 as bigint))-(((CAST(@I2nput2 as bigint))/(Power(convert(bigint,@newbase) , (@I2length2-@I2+1)))))*(Power(convert(bigint,@newbase) , (@I2length2-@I2+1))))/ (isnull(Nullif(Power(convert(bigint,@newbase) , (@I2length2-@I2)),0),1)) ,'') as varchar(100)) as nvarchar(450))))
END
Declare @Result nvarchar(100) =( select replace(ltrim(replace(Left(@Formula2,Len(@Formula2)-1),'0',' ')),' ','0'))
Return @Result
End

现在如果我跑

select dbo.Unit_Base_To_Base('101',2, 10)

然后返回5，可以使用有效的基数2输入值

和

select dbo.Unit_Base_To_Base('FFF',2, 10)

然后返回105，这是无效基数2输入值的结果

我需要确保输入值对基值有效否则返回错误

Thanks in Advance

Answer 1

有趣的问题。您可以分解输入字符串并将每个字符串放在循环中以检查它是否大于允许的“max char”。你可以通过使用char（x）函数来获得它。

http://technet.microsoft.com/pt-br/library/ms187323.aspx

下面有一些伪代码（C＃样式）

function validinputstring(stringInput, base)
{
    foreach charX in stringInput
    {
       is charX > char(base+offset)
    }
}

该偏移意味着：'1'= char（2 + offset）＆amp;＆amp; 'F'= char（16 + offset）等

如何验证字符串是否包含特定的字符范围

1 个答案: