How to enable or disable the form elements using jquery

If you want to disable or enable the form elements according to id or name under certain conditions using jquery below sample may help you to some extent.
Enable or Disable the form elements according to name

 $('input[type=submit]').attr("disabled","disabled"); //Disable
                  $('input[type=submit]').removeAttr('disabled');             //enable
                  $('input[type=text]').attr("disabled","disabled");           //Disable textbox

Getting Value of the select box and text box:

var selected_value =  $("select[name='name_of_selectbox'] option:selected").val();
var selected_value_of_textbox =  $("input[name='name_of_selectbox'] ").val();
var selected_value_of_textbox1 =  $("input#id_of_textbox ").val();

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