JAVASCRIPT

jquery disable all input form

//In older versions you could use attr. 
//As of jQuery 1.6 you should use prop instead:
$("#target :input").prop("disabled", true);

//To disable all form elements inside 'target'. See :input:
//Matches all input, textarea, select and button elements.

//If you only want the <input> elements:
$("#target input").prop("disabled", true);

jquery disable form element

// Disable #x
$( "#x" ).prop( "disabled", true );
 
// Enable #x
$( "#x" ).prop( "disabled", false );

jquery disable all forms

$("#myForm :input").prop("disabled", true);