how to disable textbox using checkbox in jquery code example

Example 1: disable textbox jquery

$("#radiobutt input[type=radio]").each(function(i){
    $(this).click(function () {
        if(i==2) { //3rd radiobutton
            $("#textbox1").attr("disabled", "disabled"); 
            $("#checkbox1").attr("disabled", "disabled"); 
        }
        else {
            $("#textbox1").removeAttr("disabled"); 
            $("#checkbox1").removeAttr("disabled"); 
        }
      });

  });

Example 2: jquery disable checkbox

$(function() {
  enable_cb();
  $("#group1").click(enable_cb);
});

function enable_cb() {
  if (this.checked) {
    $("input.group1").removeAttr("disabled");
  } else {
    $("input.group1").attr("disabled", true);
  }
}