How to build a date from separate data with google app script? - google-apps-script

Question

In my first sheet I have this:
E21: 1 juin 2020
G21: 09
H21: h
I21: 02
I want to keep this in the first sheet but In the second sheet I want this:
B3: 2020-06-01 09:02
I try this:
// I recover my sheet
var ss_evenement = SpreadsheetApp.getActive().getSheetByName('Evenement');
// I get my date
var dateDebut = ss_evenement.getRange('E21').activate().getValue();
// I put my date in sting
var dateDebutSTR = dateDebut.toString();
// I found the day of my date : with getDay I have the day of the week
var jourDebut = dateDebutSTR.substring(8,10);
// I found the month
var moisDebut = dateDebut.getMonth().toString();
// I found the Year
var anneeDebut = dateDebut.getYear().toString();
// I read the hours
var heureDebut = ss_evenement.getRange('G21').activate().getValue();
// I read the minutes
var minuteDebut = ss_evenement.getRange('I21').activate().getValue();
// I recreate my date
var dateheureDebut = new Date(anneeDebut, moisDebut, jourDebut, heureDebut, minuteDebut, "00", "00");
// I select the sheet to writing
var ss_calendrier = SpreadsheetApp.getActive().getSheetByName('Calendrier');
// I write my new date in my new sheet
ss_calendrier.getRange('B4').activate().setValue(dateheureDebut);
In debug I have:
dateDebut->Date (541813791)->Thu Apr 02 2020 03:00:00 GMT-0400 (EDT)
dateDebutSTR->String->"Thu Apr 02 2020 03:00:00 GMT-0400 (EDT)"
jourDebut->String->"02"
moisDebut->String->"3"
anneeDebut->String->"2020"
heureDebut->String->"09"
minuteDebut->String->"02"
dateheureDebut->Date (541917478)->Thu Apr 02 2020 09:02:00 GMT-0400 (EDT)
And in true, in the second file I have:
01/06/2020 06:02
The hour et the format is not good.

Answer 1

Try this:
function whoknowswhat() {
var mA=['jan','feb','mar','apl','may','jun','jul','aug','sep','oct','nov','dec'];
var ss=SpreadsheetApp.getActive();
var sh=ss.getSheetByName('Evenement');
var dt=sh.getRange('E21').getValue().trim();
var year=dt.slice(6);
var month=mA.indexOf(dt.slice(2,5));
var day=parseInt(dt.slice(0,2));
var hour=sh.getRange('G21').getValue().trim();
var minute=sh.getRange('I21').getValue().trim();
var dateheureDebut=new Date(year,month,day,hour,minute, 0);
var ss_calendrier=SpreadsheetApp.getActive().getSheetByName('Calendrier');
ss_calendrier.getRange('B4')setValue(dateheureDebut);
}

Answer 2

You can use the method getDisplayValue() to obtain the value that is displayed in the Sheet. Afterwards, it is easier to parse it and generate the final string from its data. You can see an example using this technique below:
function copyDate() {
var evenementSheet = SpreadsheetApp.getActive().getSheetByName('Evenement');
var months = ["janvier", "février", "mars", "avril", "mai", "juin", "juillet", "août", "septembre", "octobre", "novembre", "décembre"];
var dateValues = evenementSheet.getRange('B7').getDisplayValue().split(' ');
var anne = dateValues[2];
var jour = dateValues[0];
var mois = months.indexOf(dateValues[1])+1;
var heure = evenementSheet.getRange('G21').getDisplayValue();
var minute = evenementSheet.getRange('I21').getDisplayValue();
var result = Utilities.formatString('%s-%s-%s %s:%s',
anne,
mois.length > 1 ? mois : '0' + mois,
jour.length > 1 ? jour : '0' + jour,
heure,
minute);
var calendrierSheet = SpreadsheetApp.getActive().getSheetByName('Calendrier');
calendrierSheet.getRange('B4').setValue(result);
}