Google sheets script onEdit of form response clear cells - google-apps-script

Question

I am trying to make a Google script to run on form edit but not sure if it would be onEdit or onSubmit when a person edits their Google form through the Google edit URL with new answers at a later date.
I need to grab the row their response is on and clear contents of cells AO, AP, AQ, and AR only.
I know this has to be a big mess up but I am trying. Here is what I have so far:
function onEdit(e) {
var sheet = SpreadsheetApp.getActiveSheet();
var editRange = sheet.getActiveRange();
var editRow = editRange.getRow();
var editCol = editRange.getColumn();
var range = sheet.getRange("A2:AL");
var rangeRowStart = range.getRow();
var rangeRowEnd = rangeRowStart + range.getHeight()-1;
var rangeColStart = range.getColumn();
var rangeColEnd = rangeColStart + range.getWidth()-1;
if (editRow >= rangeRowStart && editRow <= rangeRowEnd
&& editCol >= rangeColStart && editCol <= rangeColEnd)
{
var ss = e.range.getSheet();
ss.getRange(thisRow,"AO" & i & ":AR" & i) // Get cells in range AO,AP,AQ,AR to clear out
.clearContent();
}
};

Answer 1

I have started over again. I have this script working but not the way needed quite yet. I need it to only clear contents of the cell (AH) for the row where firstdate != secdate. Right now it clears all cells of column AH when one cell meets the criteria.
function compareClear() {
var ss = SpreadsheetApp.getActiveSpreadsheet();
var sheet = ss.getSheetByName("Sheet1");
var firstdate = sheet.getRange("E3:E").getValues();
var secdate = sheet.getRange("AG3:AG").getValues();
if(firstdate != secdate){
SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Sheet1").getRange("AH3:AH").clearContent();
}
}

Answer 2

Just in case anyone else might need a helping hand on this subject:
The script with a big helping hand from Spencer in Google Docs forum and some added changes by me works like a charm. It may not be the prettiest script but it does what I need.
function compareClear() {
var ss = SpreadsheetApp.getActiveSpreadsheet();
var sheet = ss.getSheetByName("Form Responses 1");
var firstdate;
var secdate;
for (var i = 3; i < sheet.getLastRow(); i++) {
firstdate = new Date(sheet.getRange(i, 4).getValue());
secdate = new Date(sheet.getRange(i, 45).getValue());
if(firstdate > secdate){
sheet.getRange(i, 41).clearContent();
sheet.getRange(i, 42).clearContent();
sheet.getRange(i, 43).clearContent();
sheet.getRange(i, 44).clearContent();
}
}
}