Today, one of our BizTalk developers asked me how to take a delimited string stored in a single node, and extract all those values into separate destination nodes. I put together a quick XSLT operation that makes this magic happen.
So let’s say I have a source XML structure like this:
I need to get this pipe-delimited value into an unbounded destination node. Specifically, the above XML should be reshaped into the format here:
Notice that each pipe-delimited value is in its own “value” node. Now I guess I could chained together 62 functoids to make this happen, but it seemed easier to write a bit of XSLT that took advantage of recursion to split the delimited string and emit the desired nodes.
My map has a scripting functoid that accepts the three values from the source (included the pipe-delimited “values” field) and maps to a parent destination record.
Because I want explicit input variables to my functoid (vs. traversing the source tree just to get the individual nodes I need), I’m using the “Call Templates” action of the Scripting functoid.
My XSLT script is as follows:
<!-- This template accepts three inputs and creates the destination "Property" node. Inside the template, it calls another template which builds up the potentially repeating "Value" child node --> <xsl:template name="WritePropertyNodeTemplate"> <xsl:param name="name" /> <xsl:param name="type" /> <xsl:param name="value" /> <!-- create property node --> <Property> <!-- create single instance children nodes --> <Name><xsl:value-of select="$name" /></Name> <Type><xsl:value-of select="$type" /></Type> <!-- call splitter template which accepts the "|" separated string --> <xsl:call-template name="StringSplit"> <xsl:with-param name="val" select="$value" /> </xsl:call-template> </Property> </xsl:template> <!-- This template accepts a string and pulls out the value before the designated delimiter --> <xsl:template name="StringSplit"> <xsl:param name="val" /> <!-- do a check to see if the input string (still) has a "|" in it --> <xsl:choose> <xsl:when test="contains($val, '|')"> <!-- pull out the value of the string before the "|" delimiter --> <Value><xsl:value-of select="substring-before($val, '|')" /></Value> <!-- recursively call this template and pass in value AFTER the "|" delimiter --> <xsl:call-template name="StringSplit"> <xsl:with-param name="val" select="substring-after($val, '|')" /> </xsl:call-template> </xsl:when> <xsl:otherwise> <!-- if there is no more delimiter values, print out the whole string --> <Value><xsl:value-of select="$val" /></Value> </xsl:otherwise> </xsl:choose> </xsl:template>
Note that I use recursion to call the “string splitter” template and I keep passing in the shorter and shorter string into the template. When I use this mechanism, I end up with the destination XML shown at the top.
Any other way you would have done this?
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