原文:
SQL 将URL编码转汉字!
-- ============================================= -- 作 者: ruijc -- 描 述: 将Url编码转明文字符串 -- ============================================= CREATE FUNCTION FN_URLDecode ( @Str VARCHAR(8000)--已经编码的字符串 ) RETURNS VARCHAR(8000) AS BEGIN DECLARE @Position INT; --'%'字符所在位置 DECLARE @Chr CHAR(16); --字符常量 DECLARE @Pattern CHAR(21); DECLARE @ParseStr VARCHAR(8000);--解码后的字符串 DECLARE @Hex UNIQUEIDENTIFIER;--定义16进制模板,因为GUID方便转为BYTE DECLARE @CurrWord INT ;--当前字 DECLARE @BitsCount INT ;--当前解码位数 DECLARE @HightByte TINYINT;--高位字节 DECLARE @LowByte TINYINT;--低位字节 /****************变量初始化***********************/ SET @Chr = '0123456789abcdef'; SET @Pattern = '%[%][a-f0-9][a-f0-9]%'; SET @ParseStr=@Str; SET @Hex= '00000000-0000-0000-0000-000000000000'; SET @CurrWord=0; SET @BitsCount=0; SET @HightByte=0; SET @LowByte=0; IF (@Str IS NOT NULL OR @Str<>'') BEGIN SET @Position = PATINDEX(@Pattern, @ParseStr);--取得第一个'%'所在的位置 WHILE @Position>0 BEGIN SET @Hex=STUFF(@Hex,7,2,LEFT(RIGHT(@ParseStr,len(@ParseStr) - @Position),2)); SET @HightByte=CAST(CAST(@Hex AS BINARY(1)) AS INT); IF (@HightByte & 127=@HightByte) BEGIN--ASCII码直接转为UTF-8或UTF-16 SET @CurrWord=@HightByte; SET @BitsCount=1; END IF (@HightByte & 192=192) BEGIN--Unicode编码 SET @CurrWord=@HightByte & 31 ; SET @BitsCount=2; END IF (@HightByte & 224=224) BEGIN--UTF-8编码 SET @CurrWord = @HightByte & 15 SET @BitsCount = 3 END IF (@HightByte & 240=240) BEGIN--UTF-16编码 SET @CurrWord = @HightByte & 7 SET @BitsCount = 4 END DECLARE @Index INT; DECLARE @NEWCHAR NVARCHAR(2); SET @Index=1; SET @NEWCHAR=''; WHILE @Index<@BitsCount BEGIN IF (LEN(@ParseStr)-@Position-3*@Index)<0 BEGIN SET @ParseStr=@Str ; SET @Position=0; BREAK; END SET @NEWCHAR = LEFT(RIGHT(@ParseStr,LEN(@ParseStr) - @Position - 3* @Index),2); --如果没有16进制编码则中断外层WHILE IF @NEWCHAR NOT LIKE '[a-f0-9][a-f0-9]' BEGIN SET @ParseStr = @Str SET @Position=0;--中断外层WHILE BREAK; END SET @Hex = STUFF(@Hex, 7, 2, @NEWCHAR) SET @LowByte = CAST(CAST(@Hex AS BINARY(1)) AS INT); IF @LowByte&192=192 BEGIN SET @ParseStr = @Str SET @Position=0;--中断外层WHILE BREAK; END SET @CurrWord = (@CurrWord * 64) | (@LowByte & 63) SET @Index =@Index+ 1 END IF @BitsCount > 1 SET @ParseStr = STUFF(@ParseStr, @Position, 3*(@BitsCount), NCHAR(@CurrWord)) ELSE BEGIN set @ParseStr = STUFF(@ParseStr, @Position, 2, NCHAR(@CurrWord)) set @ParseStr = STUFF(@ParseStr, @Position+1, 1, N'') END ----取得下一个'%'所在的位置 SET @Position = PATINDEX(@Pattern, @ParseStr); END END RETURN @ParseStr; END GO SELECT dbo.FN_URLDecode('%E4%BD%A0%E6%98%AF%E5%93%AA%E4%B8%AA')