How do I skip blank cells using MailApp.SendEmail? - google-apps-script

Question

I've been using Google form to collect information to a workbook, then using that information to send customized emails back to the sender. I am a noob at coding, but I have managed to cobble together enough for this task. My problem is that, when it comes to a blank email cell it stops. I've tried to put in a loop to make it skip, with no success. Any help would be appreciated. This is the program I am using without a loop.
// This constant is written in column C for rows for which an email
// has been sent successfully.
var EMAIL_SENT = "EMAIL_SENT";
function sendEmails2() {
var sheet = SpreadsheetApp.getActiveSheet();
var startRow = 2; // First row of data to process
var numRows = 2000; // Number of rows to process
// Fetch the range of cells A2:B2001
var dataRange = sheet.getRange(startRow, 1, numRows, 2001)
// Fetch values for each row in the Range.
var data = dataRange.getValues();
for (var i = 0; i < data.length; ++i) {
var row = data[i];
var emailAddress = row[0]; // First column
var message = row[1]; // Second column
var emailSent = row[2]; // Third column
if (emailSent != EMAIL_SENT) { // Prevents sending duplicates
var subject = "Bounce Reply";
MailApp.sendEmail(emailAddress, subject, message);
sheet.getRange(startRow + i, 3).setValue(EMAIL_SENT);
// Make sure the cell is updated right away in case the script is interrupted
SpreadsheetApp.flush();
}
}
}

Answer 1

You can use string.match() function to determine if a cell is empty or not. Since you are looking for email address you might as well see if the cell has '#' sign. If not exclude the cell and continue on to the next cell like so:
if (emailAddress.match('#') === null){
continue; // skip this iteration of the loop and go to the next one
}
Your final code will look like:
var EMAIL_SENT = "EMAIL_SENT";
function sendEmails2() {
var sheet = SpreadsheetApp.getActiveSheet();
var startRow = 2; // First row of data to process
var numRows = 2000; // Number of rows to process
// Fetch the range of cells A2:B2001
var dataRange = sheet.getRange(startRow, 1, numRows, 2001)
// Fetch values for each row in the Range.
var data = dataRange.getValues();
for (var i = 0; i < data.length; ++i) {
var row = data[i];
var emailAddress = row[0] // First column
if (emailAddress.match('#') === null){
continue; // skip this iteration of the loop and go to the next one
};
var message = row[1]; // Second column
var emailSent = row[2]; // Third column
if (emailSent != EMAIL_SENT) { // Prevents sending duplicates
var subject = "Bounce Reply";
MailApp.sendEmail(emailAddress, subject, message);
sheet.getRange(startRow + i, 3).setValue(EMAIL_SENT);
// Make sure the cell is updated right away in case the script is interrupted
SpreadsheetApp.flush();
}
}
}
Edit
To check if something is empty or not you can try something like this.
if (message.match(/[a-zA-Z0-9_]/) === null) { //" /[a-zA-Z0-9_]/ " is regex to match any and every alphanumeric letter including underscore
continue; // skip this iteration of the loop and go to the next one
}
You can find more details on function match and regex here.
Hope that helps!