分享：实现其他进制数与二进制数的转化

nianran520 2010-01-07 11:10:21

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/*====================================================*/

-- Author: Ken Wong

-- Create date: 2010-01-07 23:01:08

-- Description:	将其他进制数转化为二进制数

-- select dbo.convertobinary('18',10)



/*====================================================*/

--@number 要转化的数值 @type原进制类型

create function dbo.convertobinary (@number varchar(30),@type int)

returns varchar(30)

as

begin

	declare @return varchar(30),@i int

	select @return='',@i=1

	if @type=2

	begin

		select @return=@number

	end

	else if @type=8

	begin

		while @i<=len(@number)

		begin

			select @return=@return+case substring(@number,@i,1) when '0' then '000' 

				when '1' then '001' when '2' then '010' when '3' then '011'

				when '4' then '100' when '5' then '101' when '6' then '110' 

				when '7' then '111' end

			select @i=@i+1

		end

	end

	else if @type=10

	begin

		while cast(@number as int)>=1

		begin

			select 	@return=ltrim(cast(@number as int)%2)+@return

			select @number=ltrim((cast(@number as int)-cast(@number as int)%2)/2)

		end

	end

	else if @type=16

	begin

		while @i<=len(@number)

		begin

			select @return=@return+case substring(@number,@i,1) when '0' then '0000' 

				when '1' then '0001' when '2' then '0010' when '3' then '0011'

				when '4' then '0100' when '5' then '0101' when '6' then '0110' 

				when '7' then '0111' when '8' then '1000' when '9' then '1001' 

				when 'A' then '' when 'B' then '1011' when 'C' then '1100' 

				when 'D' then '1101' when 'E' then '1110' when 'F' then '1111' end

			select @i=@i+1

		end

	end

	return @return

end