Automatically Create named ranges for each column (First row assumed to be header)

auto_referesh_google_sheet_ranges_from_column_headers.js

/** 
* Automatically Create named ranges for each column
*
* NOTE THAT IT DESTORYS ALL OTHER NAMED RANGES ON EVERY EDIT IN EVERY SHEET
*
* Public Domain by Ori Pekelman (2017) 
**/


function addNamedRanges(SS, s, number_of_sheets){
  var sheet_name = s.getName();
  var range = s.getRange(sheet_name+'!1:1'); // First row of current sheet
  var numRows = s.getLastRow();
  var numCols = range.getNumColumns();
  var first_row =1;
  for (var col = 1; col <= numCols; col++) {
    var cell = range.getCell(first_row,col);
    var columnName = cell.getValue();
    var column = columnToLetter(cell.getColumn());
    if (number_of_sheets > 0 ){  var prefix =  sheet_name.replace(/\W/g, '') + "_"} else {  var prefix = "";} // Add sheet name prefix if more than one
    var named_range = prefix + columnName.replace(/\W/g, ''); // Alpha Numeric Only
    if (columnName) {
      var range_a1notation = column + "2:" + column + numRows;
      var range_to_name = s.getRange(range_a1notation);
      SS.setNamedRange(named_range, range_to_name);  // update 
    }
  }

};

function columnToLetter(column)
{
  var temp, letter = '';
  while (column > 0)
  {
    temp = (column - 1) % 26;
    letter = String.fromCharCode(temp + 65) + letter;
    column = (column - temp - 1) / 26;
  }
  return letter;
}

function refreshNamedRanges(){
  var SS = SpreadsheetApp.getActive();
  var sheets = SS.getSheets();
  deleteNamedRanges(SS, sheet);
  for (var s in sheets){
   var sheet=sheets[s];
    addNamedRanges(SS, sheet, sheets.length);
  }
}


function deleteNamedRanges(SS){
  // The code below will delete all the named ranges in the spreadsheet.
  var namedRanges = SS.getNamedRanges();
  for (var i = 0; i < namedRanges.length; i++) {
    namedRanges[i].remove();
  }
}


function onEdit() {
  var entries = [{
    name : "Refresh Named Ranged",
    functionName : "refreshNamedRanges"
  }];
  SS.addMenu("Script", entries);
};