Some web services define inout and out parameters. You use out parameters to pass a placeholder for a return value to a web service. The web service then returns its result by writing it to the out parameter. Inout parameters let you pass a value to a web service and lets the web service return its result by overwriting the parameter value.

The following example shows a web service that takes as input an inout parameter containing a string and writes its results back to the string:

<cfset S="foo">
<cfscript>
    ws=createobject("webservice", "URLtoWSDL")
    ws.modifyString("S");
</cfscript>
<cfoutput>#S#</cfoutput>

Even though this web service takes as input the value of S, because you pass it as an inout parameter, you do not enclose it in number signs.