CFLib.org – Common Function Library Project

Description:
Use getRelative() is the inverse of the ColdFusion native ExpandPath() function -- it takes an absolute file path and returns a relative path to the given file from the current template. As opposed to expandpath(), getRelative() creates a path relative to the current template, not the base template.

Return Values:
Returns a string.

Example:

<cfoutput>#getRelative('d:\temp\test.txt')#</cfoutput>

Parameters:

Full UDF Source:

/**
 * Returns a relative path from the current template to an absolute file path.
 * v2 fix by Tony Monast
 * v2.1 fix by Tony Monast to deal with situations in which the specified path was the same as the current path, resulting in an error
 * 
 * @param abspath      Absolute path. (Required)
 * @return Returns a string. 
 * @author Isaac Dealey (info@turnkey.to) 
 * @version 2, August 30, 2012 
 */
function getRelative(abspath) {
        var currentPath = ListToArray(GetDirectoryFromPath(GetBaseTemplatePath()),"\/");
        var filePath = ListToArray(abspath,"\/");
        var relativePath = ArrayNew(1);
        var pathStart = 0;
        var i = 0;

        /* Define the starting path (path in common) */
        for (i = 1; i LTE ArrayLen(currentPath); i = i + 1) {

                if (currentPath[i] NEQ filePath[i]) {
                        pathStart = i;
                        break;
                }
        }

        if (pathStart GT 0) {
                /* Build the prefix for the relative path (../../etc.) */
                for (i = ArrayLen(currentPath) - pathStart ; i GTE 0 ; i = i - 1) {
                        ArrayAppend(relativePath,"..");
                }

                /* Build the relative path */
                for (i = pathStart; i LTE ArrayLen(filePath) ; i = i + 1) {
                        ArrayAppend(relativePath,filePath[i]);
                }
        }

        /* Same level */
        else
                ArrayAppend(relativePath,filePath[ArrayLen(filePath)]);

        /* Return the relative path */
        return ArrayToList(relativePath,"/");
}