DateStamp1203

/**
* Creates a Date Stamp if a column is edited.
*/

//CORE VARIABLES
// The column you want to check if something is entered.
var COLUMNTOCHECK = 2;
// Where you want the date time stamp offset from the input location. [row, column]
var DATETIMELOCATION = [0,-1];
// Sheet you are working on
var SHEETNAME = 'Sheet1'

function onEdit(e) {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var sheet = ss.getActiveSheet();
  //checks that we're on the correct sheet.
  if( sheet.getSheetName() == SHEETNAME ) {
    var selectedCell = ss.getActiveCell();
    //checks the column to ensure it is on the one we want to cause the date to appear.
    if( selectedCell.getColumn() == COLUMNTOCHECK) {
      var dateTimeCell = selectedCell.offset(DATETIMELOCATION[0],DATETIMELOCATION[1]);
      dateTimeCell.setValue(new Date());
      }
  }
}