Answers for "dropdown change in jquery"

on change jquery

You can apply any one approach:

$("#Input_Id").change(function(){   // 1st
    // do your code here
    // When your element is already rendered
});


$("#Input_Id").on('change', function(){    // 2nd (A)
    // do your code here
    // It will specifically called on change of your element
});

$("body").on('change', '#Input_Id', function(){    // 2nd (B)
    // do your code here
    // It will filter the element "Input_Id" from the "body" and apply "onChange effect" on it
});

dropdown option selection change event in jquery

$("select [name='element_name']").change(function(){
	// condition goes here
});

change value of drop down using jquery

$('#ddlID').val('New_OptionValue').change()