sql查询结果转XML和JSON

很久之前用到的，现在整理在这，里面一些代码来源于网上，不过有些bug已被我修改了。

1.查询结果转XML

DECLARE @ParameterSQL NVARCHAR(MAX)='SELECT * FROM table';DECLARE @SQL NVARCHAR(MAX)DECLARE @XMLString VARCHAR(MAX)DECLARE @XML XMLDECLARE @Paramlist NVARCHAR(1000)SET @Paramlist = N'@XML XML OUTPUT'SET @SQL = 'WITH PrepareTable (XMLString)'SET @SQL = @SQL + 'AS( 'SET @SQL = @SQL + @ParameterSQL+ ' FOR XML RAW,TYPE,ELEMENTS'SET @SQL = @SQL + ')'SET @SQL = @SQL + 'SELECT @XML=[XMLString]FROM[PrepareTable]'EXEC sp_executesql @SQL, @Paramlist, @XML=@XML OUTPUTSET @XMLString=CAST(@XML AS VARCHAR(MAX))SELECT @XML;SELECT @XMLString;

其中@ParameterSQL为要查询的语句，@XMLXML格式数据，@XMLStringXML转成字符串

---

2.查询结果转JSON

查询结果转换成json需要经过两个步骤，首先将查询结果转成XML数据，然后通过XML数据转成json
XML转JSON的存储过程如下：

CREATE PROCEDURE [dbo].[SerializeJSON] (     @XML  XML,     @json_xml  NVARCHAR(MAX) OUTPUT    )ASBEGIN    DECLARE @XMLString NVARCHAR(MAX);    SET @XMLString = CAST(@XML AS NVARCHAR(MAX));    BEGIN TRY--//开始捕捉异常        DECLARE @JSON NVARCHAR(MAX);        DECLARE @Row VARCHAR(MAX);        DECLARE @RowStart INT;        DECLARE @RowEnd INT;        DECLARE @FieldStart INT;        DECLARE @FieldEnd INT;        DECLARE @KEY VARCHAR(MAX);        DECLARE @Value VARCHAR(MAX);        DECLARE @StartRoot VARCHAR(100);        SET @StartRoot = '<row>';        DECLARE @EndRoot VARCHAR(100);        SET @EndRoot = '</row>';        DECLARE @StartField VARCHAR(100);        SET @StartField = '<';        DECLARE @EndField VARCHAR(100);        SET @EndField = '>';        SET @RowStart = CHARINDEX(@StartRoot, @XMLString, 0);        SET @JSON = '';        WHILE @RowStart>0        BEGIN            SET @RowStart = @RowStart + LEN(@StartRoot);            SET @RowEnd = CHARINDEX(@EndRoot, @XMLString, @RowStart);            SET @Row = SUBSTRING(@XMLString, @RowStart, @RowEnd - @RowStart);            SET @JSON = @JSON + '{';            --//for each row            SET @FieldStart = CHARINDEX(@StartField, @Row, 0);            WHILE @FieldStart>0            BEGIN                --//parse node key                SET @FieldStart = @FieldStart + LEN(@StartField);                SET @FieldEnd = CHARINDEX(@EndField, @Row, @FieldStart);                DECLARE @end INT = CHARINDEX('/>', @Row, @FieldStart);                IF @end<1                    OR @end>@FieldEnd                BEGIN                    SET @KEY = SUBSTRING(@Row, @FieldStart, @FieldEnd - @FieldStart);                    SET @JSON = @JSON + '"' + @KEY + '":';                    --//parse node value                    SET @FieldStart = @FieldEnd + 1;                    SET @FieldEnd = CHARINDEX('</', @Row, @FieldStart);                    SET @Value = SUBSTRING(@Row, @FieldStart, @FieldEnd - @FieldStart);                    SET @JSON = @JSON + '"' + @Value + '",';                END;                SET @FieldStart = @FieldStart + LEN(@StartField);                SET @FieldEnd = CHARINDEX(@EndField, @Row, @FieldStart);                SET @FieldStart = CHARINDEX(@StartField, @Row, @FieldEnd);            END;            IF LEN(@JSON)>0                SET @JSON = SUBSTRING(@JSON, 0, LEN(@JSON));            SET @JSON = @JSON + '},';            --// for each row            SET @RowStart = CHARINDEX(@StartRoot, @XMLString, @RowEnd);        END;        IF LEN(@JSON)>0            SET @JSON = SUBSTRING(@JSON, 0, LEN(@JSON));        --//SET @JSON = '[' + @JSON + ']';        SET @json_xml = @JSON;    END TRY--//结束捕捉异常    BEGIN CATCH--//有异常被捕获        SET @json_xml = @XMLString;    END CATCH;--//结束异常处理END;