Verify Email Entered in a Google Form Using Google Apps Script -

Verify Email Entered in a Google Form Using Google Apps Script -

my question same question [here], asnwer given not detailed enough. want have users submit email address in google form. email address used periodically send emails people have entered information. however, don't want users able come in random email address spam people. therefore, want verify user has entered email address belonging themselves, similar things such adding secondary email address in gmail. i not want know how check proper syntax.

to rephrase: want verify email entered user belongs user.

generate random verification id var characterstouse = "0123456789abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz"; //set length of id number generate. var varlngthid = 5; var makepubid = ''; (var i=0; i<varlngthid; i++) { var randnum = math.floor(math.random() * characterstouse.length); makepubid += characterstouse.substring(randnum,randnum+1); };

and send number user in initial email. when user gets email, can come site, , come in verification code. if want check if email valid without sending email address, question has been asked here:

stackoverflow check email without sending it

email google-apps-script google-spreadsheet google-form