So I have always been bothered that if you want to create tasks via workflow, you could only set certain predefined fields.  There would always have to be some custom apex trigger running to update other fields.  I wanted to come up with a standard  way to solve this.  My thought was to use the Description/Comments field on the task to drive other fields to update.

So when using the workflow "Create a Task" screen you would add a special string to the end of the comments such as:

"My real comment is this part of the message. >>Type=Meeting::Custom_Field__c=Custom Value"

My apex trigger will take everything after the ">>" then split it based on the "::" and update the proper fields.  This code will be a huge time saver for me so I thought I would share it.

This is my first code share so feedback is appreciated.

trigger WFTaskCreationExtend on Task (before insert) {
	
for(Task t:Trigger.new){
	List<string> parsedesc = t.Description.substringAfter('>>').split('::');
	t.description=t.Description.substringBefore('>>');
	if(parsedesc[0].length()>0){
		for(string p:parsedesc){
			system.debug('Update expression: '+p);
			try{
				t.put(p.substringBefore('='), p.substringAfter('='));
			}
			catch (System.SObjectException e) {
				if(e.getMessage().contains('Decimal')){
					t.put(p.substringBefore('='), decimal.valueof(p.substringAfter('=')));
				}
				else{
					System.debug('Field Error: '+e.getMessage());
				}
			}
		}
	}
}
}