Concatenating part of a string

Question

I have this function in col A to concatenate some cells to generate an ID:

={"ID"; arrayformula(IF(C2:C="";;(LEFT(C2:C;1))&"-"&(LEFT(D2:D;1))&(LEFT(E2:E;1))&"-"&(UPPER(RIGHT(B2:B;8)))))}

I am trying to replace the function with a script but my code not works.
What is wrong?

function concatenate() {
      var sheet = SpreadsheetApp.getActiveSheet();
      var data = sheet.getDataRange().getValues();
      var lr = sheet.getLastRow()
      var values1 = sheet.getSheetValues(2, 3, lr, 1);
      var values2 = sheet.getSheetValues(2, 4, lr, 1);
      var values3 = sheet.getSheetValues(2, 5, lr, 1);
      var values4 = sheet.getSheetValues(2, 2, lr, 1);
      var results = [];
      for (var i = 0; i < lr; i++) {
        results.push([values1[i][0].slice(0,1) + "-" + values2[i][0].slice(0,1) + values3[i][0].slice(0,1) + "-" + values4[i][0].slice(-8)]);
      }
      sheet.getRange(2, 1, results.length).setValues(results);
    }

P.S.
How can I also run the script every time there is an edit on a row?

Answer 1

Are sure that this isn't what you want?

function concatenate() {
  var sheet = SpreadsheetApp.getActiveSheet();
  var data = sheet.getDataRange().getValues();
  var results = [];
  for (var i=1;i<data.length; i++) {//if you have a header row start from one
    results.push([data[i][2].slice(0,1) + "-" + data[i][3].slice(0,1) + data[i][4].slice(0,1) + "-" + data[i][1].slice(-8)]);
  }
  sheet.getRange(2, 1, results.length,1).setValues(results);
}