在这个例子中最好抛出异常的地方？(Where best to throw exception in this example?)

 这里是你的数组和循环的代码： 
 
function Transfer() {

  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var s1 = ss.getSheetByName('Monday-Saturday');
  var s2 = ss.getSheetByName('2ndTrailer');

  var data1 = s1.getRange(5, 3, 18, 2).getValues();
  var data2 = s2.getRange(3, 2, 18, 2).getValues();
  var newData = [];

  for(var i = 0 ; i < data1.length; i++){

    var newValueC = data1[i][0] + data2[i][1];
    var newValueD = data1[i][1] + data2[i][1];

    newData.push([newValueC, newValueD]);

  }

  s1.getRange(5, 3, 18, 2).setValues(newData);

  s2.getRange('A2').clearContent();
  s1.getRange('A23').setValue('YES');

}
 
 有点难看，但应该做的伎俩。 
 
 编辑：做了一些更改，因为range.setValue（）方法导致问题 

Here is your code with arrays and loop :
 
function Transfer() {

  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var s1 = ss.getSheetByName('Monday-Saturday');
  var s2 = ss.getSheetByName('2ndTrailer');

  var data1 = s1.getRange(5, 3, 18, 2).getValues();
  var data2 = s2.getRange(3, 2, 18, 2).getValues();
  var newData = [];

  for(var i = 0 ; i < data1.length; i++){

    var newValueC = data1[i][0] + data2[i][1];
    var newValueD = data1[i][1] + data2[i][1];

    newData.push([newValueC, newValueD]);

  }

  s1.getRange(5, 3, 18, 2).setValues(newData);

  s2.getRange('A2').clearContent();
  s1.getRange('A23').setValue('YES');

}
 
A bit ugly, but should do the trick.
 
Edit: Made a few changes, since the range.setValue() method causing problems