CFLib.org – Common Function Library Project

Description:
Generate a random key; the format of which can be based on a specific set of business rules such as numeric, string, alphanumeric and special characters. You can return lower, upper or mixed case + more options

Return Values:
returns a string.

Example:

myKey = generateRandomKey();
myKey = generateRandomKey(case="mixed", format="alphanumeric", length="8");

Parameters:

Full UDF Source:

<!---
 Generate a random key with options
 
 @param case      upper, lower, or mixed case - defaults upper (Optional)
 @param format      numeric, string, alphanumeric or special (Optional)
 @param length      length of key to generate (Optional)
 @param specialChars      ist of special chars to help generate key from (Optional)
 @param fixedPrefix      A prefix prepended to the generated key (Optional)
 @param fixedSuffix      A suffix appended to the generated key (Optional)
 @return returns a string. 
 @author Michael Sharman (michael@chapter31.com) 
 @version 0, May 9, 2009 
--->
<cffunction name="generateRandomKey" access="public" output="false" returntype="string">
    <cfargument name="case" type="string" default="upper" hint="Whether upper, lower or mixed" />
    <cfargument name="format" type="string" default="alphanumeric" hint="Whether to generate numeric, string, alphanumeric or special (includes alphanumeric and special characters such as ! @ & etc)" />
    <cfargument name="invalidCharacters" type="string" default="" hint="List of invalid characters which will be excluded from the key. This overrides the default list" />
    <cfargument name="length" type="numeric" default="8" hint="The length of the key to generate" />
    <cfargument name="numericPrefix" type="numeric" default="0" hint="Number of random digits to start the key with (the rest of the key will be whatever the 'format' is)" />
    <cfargument name="numericSuffix" type="numeric" default="0" hint="Number of random digits to end the key with (the rest of the key will be whatever the 'format' is)" />
    <cfargument name="fixedPrefix" type="string" default="" hint="A prefix prepended to the generated key. The length of which is subtracted from the 'length' argument" />
    <cfargument name="fixedSuffix" type="string" default="" hint="A suffix appended to the generated key. The length of which is subtracted from the 'length' argument" />
    <cfargument name="specialChars" type="string" default="" hint="List of special chars to help generate key from. Overrides the default 'characterMap.special' list" />
    <cfargument name="debug" type="boolean" default="false" hint="Returns cfcatch information in the event of an error. Try turning on if function returns no value." />

    <cfscript>
                        
        var i = 0;
        var key = "";
        var keyCase = arguments.case;
        var keyLength = arguments.length;
        var uniqueChar = "";
        var invalidChars = "o,i,l,s,O,I,L,S";    //Possibly confusing characters we will remove
        var characterMap = structNew();
        var characterLib = "";
        var libLength = 0;
        
        try
        {
            
            characterMap.numeric = "0,1,2,3,4,5,6,7,8,9";
            characterMap.stringLower = "a,b,c,d,e,f,g,h,i,j,k,l,m,n,o,p,q,r,s,t,u,v,w,x,y,z";
            characterMap.stringUpper = UCase(characterMap.stringLower);
            characterMap.stringCombined = listAppend(characterMap.stringLower, characterMap.stringUpper);
                        
            if (len(trim(arguments.specialChars)))
                characterMap.special = arguments.specialChars;
            else
                characterMap.special = "!,@,##,$,%,^,&,*,(,),_,-,=,+,/,\,[,],{,},<,>,~";

            switch (arguments.format)
            {
                case "numeric":
                    characterLib = characterMap.numeric;            
                    break;
                case "string":
                    if (keyCase EQ "upper")
                    {
                        characterLib = characterMap.stringUpper;
                    }                
                    else if (keyCase EQ "lower")
                    {
                        characterLib = characterMap.stringLower;
                    }                
                    else if (keyCase EQ "mixed")
                    {
                        characterLib = characterMap.stringCombined;
                    }
                    break;
                case "alphanumeric":
                    invalidChars = invalidChars.concat(",0,1,5");        //Possibly confusing chars removed
                    if (keyCase EQ "upper")
                    {
                        characterLib = listAppend(characterMap.numeric, characterMap.stringUpper);
                    }
                    else if (keyCase EQ "lower")
                    {
                        characterLib = listAppend(characterMap.numeric, characterMap.stringLower);
                    }                
                    else if (keyCase EQ "mixed")
                    {
                        characterLib = listAppend(characterMap.numeric, characterMap.stringCombined);
                    }
                    break;
                case "special":
                    invalidChars = invalidChars.concat(",0,1,5");        //Possibly confusing chars removed
                    if (keyCase EQ "upper")
                    {
                        characterLib = listAppend(listAppend(characterMap.numeric, characterMap.stringUpper), characterMap.special);
                    }
                    else if (keyCase EQ "lower")
                    {
                        characterLib = listAppend(listAppend(characterMap.numeric, characterMap.stringLower), characterMap.special);
                    }                    
                    else if (keyCase EQ "mixed")
                    {
                        characterLib = listAppend(listAppend(characterMap.numeric, characterMap.stringCombined), characterMap.special);
                    }
                    break;
            }
    
            if (len(trim(arguments.invalidCharacters)))
                invalidChars = arguments.invalidCharacters;
    
            if (len(trim(arguments.fixedPrefix)))
            {
                key = arguments.fixedPrefix;
                keyLength = keyLength - len(trim(arguments.fixedPrefix));
            }
            
            if (len(trim(arguments.fixedSuffix)))
            {
                keyLength = keyLength - len(trim(arguments.fixedSuffix));
            }
        
            libLength = listLen(characterLib);
    
            for (i = 1;i LTE keyLength;i=i+1)
            {
                do
                {
                    if (arguments.numericPrefix GT 0 AND i LTE arguments.numericPrefix)
                    {
                        uniqueChar = listGetAt(characterMap.numeric, randRange(1, listLen(characterMap.numeric)));
                    }
                    else if (arguments.numericSuffix GT 0 AND keyLength-i LT arguments.numericSuffix)
                    {
                        uniqueChar = randRange(characterMap.numeric, randRange(1, listLen(characterMap.numeric)));
                    }
                    else
                    {
                        uniqueChar = listGetAt(characterLib, randRange(1, libLength));
                    }
                }
                while (listFind(invalidChars, uniqueChar));                
                key = key.concat(uniqueChar);
            }
            
            if (len(trim(arguments.fixedSuffix)))
                key = key.concat(trim(arguments.fixedSuffix));

        }
        catch (Any e)
        {
            if (arguments.debug)
                key = e.message & " " & e.detail;
            else
                key = "";
        }

        return key;
        
    </cfscript>

</cffunction>