google script reject spreadsheet submit - google-apps-script

Question

I have a function in a spreadsheet based script that is triggered when a submission is made with the spreadsheet form :
function onEntry(e){
Logger.log(e);
MailApp.sendEmail("scriptadmin#uniben.edu", "New Mail Request", "Someone submited data");
}
How can I reject the entry, say if it's a duplicate entry ?

Answer 1

Using the documentation on events you will have to choose what data you want check (user name, specific field...) and compare that to data already in the spreadsheet.
You should do these iterations on an array level since it will be far more efficient and fast, you can get data in an array using something like
var data = SpreadsheetApp.openById(key).getDataRange().getValues();
You could also use javascript function like indexOf() that will return -1 if no match if found or item position in the array if a match is found.
Actually there are many ways to do that but your question is too vague to know what will be the best...
EDIT : following your comment, I'd suggest you let the duplicate form data come into the sheet and then use a script to remove duplicates. You could run this script on a on form submit trigger or on a timer to let it run daily or hourly, and send the email only if the last entry was a new one (no duplicates found)... depending on your use case.
There is a script in the gallery that does the job pretty well, it was written by Romain Vialard, a GAS TC that has contributed a lot. (the link above goes to the script description but you can get it also in the public gallery, just search for 'remove duplicates' you'll see that other scripts do that, all the scripts in the gallery have been checked by the GAS team)

Answer 2

4 months late, but better late than never. I believe this function does almost what was originally requested. i.e. "How do I prevent the entry from entering the spreadsheet if I decide that it's a duplicate." It is not precisely what was requested, but very close.
This code checks one column against that same column in another sheet, for all rows in that sheet. Lets say you have a list of companies or clients on a sheet. That list includes name, phone, address, etc. etc. Lets say you want to check against the phone number - if the phone number you are currently entering is already on your client sheet, then don't allow entry - or more precisely clear it out immediately upon entering it.
I'm sure the more experienced members will be able to point out flaws, but it works for me.
I believe it will also work for the case where a phone number in the middle of the sheet is changed - so it's not just last line that gets checked, it's the line that gets edited that gets checked - I've not tested this particlar scenario. Also, I made some changes to variable names to protect the innocent...hopefully I didn't mess anything up while doing that.
I call this function from within another function that is triggered by onEdit. Theoretically it should be able to be installed as an onEdit trigger itself. I hope someone finds it useful.
function checkNewEntryForDuplicate(e) {
var ss = SpreadsheetApp.getActiveSpreadsheet();
var entrySheet = SpreadsheetApp.getActiveSheet();
var clientSheet = ss.getSheetByName("Clients");
var r = entrySheet.getActiveCell();
var lastCol = entrySheet.getLastColumn();
// If this had any consistency, we'd be able to get the row from entrySheet the same
// as we get column. But there is no getRow() method at the sheet level.
var rowNum = r.getRow();
var clientData=clientSheet.getDataRange().getValues();
var phoneColumnOffset=getPhoneColumnOffset(); // You'll need to get the offset elsewhere. I have a function that does that.
var columnNum=e.range.getColumn(); // column that is currently being edited
if (columnNum != phoneColumnOffset+1) // no point in doing anything else if it's not the column we're interested in.
return 0;
var entryRow=entrySheet.getRange(rowNum, 1, 1, lastCol);
var phoneNum = e.range.getValue();
// iterate over each row in the clientData 2-dimensional array.
for(i in clientData){
var row = clientData[i];
var duplicate = false;
// For each row this conditional statement will find duplicates
if(row[phoneColumnOffset] == phoneNum){
duplicate = true;
var msg="Duplicate Detected. Please do not enter. Deleting it..."
Browser.msgBox(msg);
entryRow.clearContent();
entryRow.clearComment();
return duplicate;
}
}
return duplicate;
}

Answer 3

I am doing the same things but having no scripts at all and just by spreadsheet functions. That kind of things are just like SQL for me and very interest to do.
For your question, this link will help: http://www.labnol.org/software/find-remove-duplicate-records-google-docs/5169/