function ChangeCategoryState(sender, state) {
      changeAllCheckBoxes(state)
      return false;
  }

  function changeAllCheckBoxes(state) {
      var gridViewRows = document.getElementById("ctl00_ContentPlaceHolder1_CheckBoxListCategories").rows;
      for (var i = 0; i < gridViewRows.length; ++i) {
          for (var j = 0; j < gridViewRows[i].cells.length; ++j) {
              if (gridViewRows[i].cells[j].childNodes[0] != null) {
                  gridViewRows[i].cells[j].childNodes[0].checked = state;
              }
        }
      }
  }

  function changeAllSelectPositionCheckBoxes(state) {
      var gridViewRows = document.getElementById("ctl00_ContentPlaceHolder1_GridView1").rows;
      for (var i = 1; i < gridViewRows.length; ++i) {
          gridViewRows[i].cells[5].childNodes[0].childNodes[0].checked = state;
     }
     return false;
  }